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Glaviano A, Wander SA, Baird RD, Yap KCH, Lam HY, Toi M, Carbone D, Geoerger B, Serra V, Jones RH, Ngeow J, Toska E, Stebbing J, Crasta K, Finn RS, Diana P, Vuina K, de Bruin RAM, Surana U, Bardia A, Kumar AP. Mechanisms of sensitivity and resistance to CDK4/CDK6 inhibitors in hormone receptor-positive breast cancer treatment. Drug Resist Updat 2024; 76:101103. [PMID: 38943828 DOI: 10.1016/j.drup.2024.101103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 05/17/2024] [Accepted: 06/10/2024] [Indexed: 07/01/2024]
Abstract
Cell cycle dysregulation is a hallmark of cancer that promotes eccessive cell division. Cyclin-dependent kinase 4 (CDK4) and cyclin-dependent kinase 6 (CDK6) are key molecules in the G1-to-S phase cell cycle transition and are crucial for the onset, survival, and progression of breast cancer (BC). Small-molecule CDK4/CDK6 inhibitors (CDK4/6i) block phosphorylation of tumor suppressor Rb and thus restrain susceptible BC cells in G1 phase. Three CDK4/6i are approved for the first-line treatment of patients with advanced/metastatic hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) BC in combination with endocrine therapy (ET). Though this has improved the clinical outcomes for survival of BC patients, there is no established standard next-line treatment to tackle drug resistance. Recent studies suggest that CDK4/6i can modulate other distinct effects in both BC and breast stromal compartments, which may provide new insights into aspects of their clinical activity. This review describes the biochemistry of the CDK4/6-Rb-E2F pathway in HR+ BC, then discusses how CDK4/6i can trigger other effects in BC/breast stromal compartments, and finally outlines the mechanisms of CDK4/6i resistance that have emerged in recent preclinical studies and clinical cohorts, emphasizing the impact of these findings on novel therapeutic opportunities in BC.
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Affiliation(s)
- Antonino Glaviano
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Palermo 90123, Italy
| | - Seth A Wander
- Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Richard D Baird
- Cancer Research UK Cambridge Centre, Hills Road, Cambridge CB2 0QQ, UK
| | - Kenneth C-H Yap
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117600, Singapore; NUS Center for Cancer Research, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119077, Singapore
| | - Hiu Yan Lam
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117600, Singapore; NUS Center for Cancer Research, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119077, Singapore
| | - Masakazu Toi
- School of Medicine, Kyoto University, Kyoto, Japan
| | - Daniela Carbone
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Palermo 90123, Italy
| | - Birgit Geoerger
- Gustave Roussy Cancer Center, Department of Pediatric and Adolescent Oncology, Inserm U1015, Université Paris-Saclay, Villejuif, France
| | - Violeta Serra
- Experimental Therapeutics Group, Vall d'Hebron Institute of Oncology, Barcelona, Spain
| | - Robert H Jones
- Cardiff University and Velindre Cancer Centre, Museum Avenue, Cardiff CF10 3AX, UK
| | - Joanne Ngeow
- Lee Kong Chian School of Medicine (LKCMedicine), Nanyang Technological University, Experimental Medicine Building, 636921, Singapore; Cancer Genetics Service (CGS), National Cancer Centre Singapore, 168583, Singapore
| | - Eneda Toska
- Department of Biochemistry and Molecular Biology, Johns Hopkins School of Public Health, Baltimore, MD, USA
| | - Justin Stebbing
- School of Life Sciences, Anglia Ruskin University, Cambridge, UK; Division of Cancer, Imperial College London, Hammersmith Campus, London, UK
| | - Karen Crasta
- NUS Center for Cancer Research, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119077, Singapore; Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, 117593, Singapore; Healthy Longetivity Translational Program, Yong Loo Lin School of Medicine, National University of Singapore, 117456, Singapore
| | - Richard S Finn
- Department of Oncology, Geffen School of Medicine, University of California, Los Angeles, CA, USA
| | - Patrizia Diana
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Palermo 90123, Italy
| | - Karla Vuina
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK
| | - Robertus A M de Bruin
- MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK
| | - Uttam Surana
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117600, Singapore; SiNOPSEE Therapeutics Pte Ltd, A⁎STARTCentral, 139955, Singapore
| | - Aditya Bardia
- Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
| | - Alan Prem Kumar
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117600, Singapore; NUS Center for Cancer Research, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119077, Singapore.
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Huang H, Liu W, Lin J, Shu F, Xia Z, Zheng Y. Graphene Quantum Dots Reduce Hypertrophic Scar by Inducing Myofibroblasts To Be a Quiescent State. ACS APPLIED MATERIALS & INTERFACES 2024; 16:37530-37544. [PMID: 38989714 DOI: 10.1021/acsami.4c05731] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/12/2024]
Abstract
Contrary to the initial belief that myofibroblasts are terminally differentiated cells, myofibroblasts have now been widely recognized as an activation state that is reversible. Therefore, strategies targeting myofibroblast to be a quiescent state may be an effective way for antihypertrophic scar therapy. Graphene quantum dots (GQDs), a novel zero-dimensional and carbon-based nanomaterial, have recently garnered significant interest in nanobiomedicine, owing to their excellent biocompatibility, tunable photoluminescence, and superior physiological stability. Although multiple nanoparticles have been used to alleviate hypertrophic scars, a GQD-based therapy has not been reported. Our in vivo studies showed that GQDs exhibited significant antiscar efficacy, with scar appearance improvement, collagen reduction and rearrangement, and inhibition of myofibroblast overproliferation. Further in vitro experiments revealed that GQDs inhibited α-SMA expression, collagen synthesis, and cell proliferation and migration, inducing myofibroblasts to become quiescent fibroblasts. Mechanistic studies have demonstrated that the effect of GQDs on myofibroblast proliferation blocked cell cycle progression by disrupting the cyclin-CDK-E2F axis. This study suggests that GQDs, which promote myofibroblast-to-fibroblast transition, could be a novel antiscar nanomedicine for the treatment of hypertrophic scars and other types of pathological fibrosis.
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Affiliation(s)
- Hongchao Huang
- Department of Burn Surgery, The First Affiliated Hospital of Naval Medical University, Shanghai 200433, People's Republic of China
| | - Wenzhang Liu
- Department of Burn Surgery, The First Affiliated Hospital of Naval Medical University, Shanghai 200433, People's Republic of China
| | - Jiezhi Lin
- Department of Burn Surgery, The First Affiliated Hospital of Naval Medical University, Shanghai 200433, People's Republic of China
| | - Futing Shu
- Department of Burn Surgery, The First Affiliated Hospital of Naval Medical University, Shanghai 200433, People's Republic of China
| | - Zhaofan Xia
- Department of Burn Surgery, The First Affiliated Hospital of Naval Medical University, Shanghai 200433, People's Republic of China
- Research Unit of Key Techniques for Treatment of Burns and Combined Burns and Trauma Injury, Chinese Academy of Medical Sciences, Shanghai 200433, People's Republic of China
| | - Yongjun Zheng
- Department of Burn Surgery, The First Affiliated Hospital of Naval Medical University, Shanghai 200433, People's Republic of China
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Rezaeian AH, Inuzuka H, Wei W. Insights into the aberrant CDK4/6 signaling pathway as a therapeutic target in tumorigenesis. ADVANCES IN PROTEIN CHEMISTRY AND STRUCTURAL BIOLOGY 2022; 135:179-201. [PMID: 37061331 DOI: 10.1016/bs.apcsb.2022.11.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The recent findings advance our knowledge for the prevention of the premature activation of the major oncogenic pathways including MYC and the cyclin D-cyclin-dependent kinases 4 and 6 (CDK4/6) axis. D-type cyclins are frequently deregulated in human cancer and promote cell division in part through activation of CDK4/6. Therefore, the activation of the cyclin D-CDK4/6 axis stimulates cell proliferation and cancer progression, which represents a unique therapeutic target. However, we have shown that inhibition of CDK4/6 upregulates protein levels of RB1 and CDK6 for acquisition of drug resistance to CDK4/6 inhibitors. Here, we review new progress in the control of cyclin D-dependent cancer cell cycle and proliferation, along with identification of novel E3 ligase for the stability of cyclin D. Cullin4-RING E3 ligase (CRL4)AMBRA1 complex plays a critical role in regulating D-type cyclins through their protein destabilization to control S phase entry and maintain genomic integrity. We also summarize the strategy for inhibition of the cyclin D-associated kinases CDK4/6 and other potential cell cycle regulators for targeting cancer with altered cyclin D expression. We also uncover the function of CK1ɛ as an effective target to potentiate therapeutic efficacy of CDK4/6 inhibitors. Moreover, as the level of PD-L1 is considered in the severe clinical problem in the patients treated with CDK4 inhibitors, we assume that a therapeutic combination using PD-L1 immunotherapy might lower the development of drug resistance and targeting cyclin D will likely inhibit tumor growth and overcome resistance to cyclin D-associated CDK4/6 inhibitors.
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Affiliation(s)
- Abdol-Hossein Rezaeian
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - Hiroyuki Inuzuka
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - Wenyi Wei
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States.
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Correia L, Magno R, Xavier JM, de Almeida BP, Duarte I, Esteves F, Ghezzo M, Eldridge M, Sun C, Bosma A, Mittempergher L, Marreiros A, Bernards R, Caldas C, Chin SF, Maia AT. Allelic expression imbalance of PIK3CA mutations is frequent in breast cancer and prognostically significant. NPJ Breast Cancer 2022; 8:71. [PMID: 35676284 PMCID: PMC9177727 DOI: 10.1038/s41523-022-00435-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 03/31/2022] [Indexed: 11/09/2022] Open
Abstract
PIK3CA mutations are the most common in breast cancer, particularly in the estrogen receptor-positive cohort, but the benefit of PI3K inhibitors has had limited success compared with approaches targeting other less common mutations. We found a frequent allelic expression imbalance between the missense mutant and wild-type PIK3CA alleles in breast tumors from the METABRIC (70.2%) and the TCGA (60.1%) projects. When considering the mechanisms controlling allelic expression, 27.7% and 11.8% of tumors showed imbalance due to regulatory variants in cis, in the two studies respectively. Furthermore, preferential expression of the mutant allele due to cis-regulatory variation is associated with poor prognosis in the METABRIC tumors (P = 0.031). Interestingly, ER-, PR-, and HER2+ tumors showed significant preferential expression of the mutated allele in both datasets. Our work provides compelling evidence to support the clinical utility of PIK3CA allelic expression in breast cancer in identifying patients of poorer prognosis, and those with low expression of the mutated allele, who will unlikely benefit from PI3K inhibitors. Furthermore, our work proposes a model of differential regulation of a critical cancer-promoting gene in breast cancer.
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Affiliation(s)
- Lizelle Correia
- Faculty of Medicine and Biomedical Sciences (FMCB), Universidade do Algarve, Faro, Portugal
| | - Ramiro Magno
- Center for Research in Health Technologies and Information Systems (CINTESIS), Universidade do Algarve, Faro, Portugal
| | - Joana M Xavier
- Center for Research in Health Technologies and Information Systems (CINTESIS), Universidade do Algarve, Faro, Portugal
| | - Bernardo P de Almeida
- Faculty of Medicine and Biomedical Sciences (FMCB), Universidade do Algarve, Faro, Portugal
- The Research Institute of Molecular Pathology, Vienna, Austria
| | - Isabel Duarte
- Center for Research in Health Technologies and Information Systems (CINTESIS), Universidade do Algarve, Faro, Portugal
| | - Filipa Esteves
- Faculty of Medicine and Biomedical Sciences (FMCB), Universidade do Algarve, Faro, Portugal
- ProRegeM-PhD Program in Mechanisms of Disease and Regenerative Medicine, Universidade do Algarve, Faro, Portugal
| | - Marinella Ghezzo
- Center for Research in Health Technologies and Information Systems (CINTESIS), Universidade do Algarve, Faro, Portugal
| | - Matthew Eldridge
- Cancer Research UK Cambridge Institute, Li Ka Shing Centre, University of Cambridge, Robinson Way, Cambridge, UK
| | - Chong Sun
- Division of Molecular Carcinogenesis, The Netherlands Cancer Institute, Amsterdam, The Netherlands
- DKFZ, Heidelberg, Germany
| | - Astrid Bosma
- Division of Molecular Carcinogenesis, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Lorenza Mittempergher
- Division of Molecular Carcinogenesis, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Ana Marreiros
- Faculty of Medicine and Biomedical Sciences (FMCB), Universidade do Algarve, Faro, Portugal
| | - Rene Bernards
- Division of Molecular Carcinogenesis, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Carlos Caldas
- Cancer Research UK Cambridge Institute, Li Ka Shing Centre, University of Cambridge, Robinson Way, Cambridge, UK
- Department of Oncology, University of Cambridge, Cambridge, UK
- Cancer Research UK Cambridge Cancer Centre, Cambridge, UK
| | - Suet-Feung Chin
- Cancer Research UK Cambridge Institute, Li Ka Shing Centre, University of Cambridge, Robinson Way, Cambridge, UK.
- Department of Oncology, University of Cambridge, Cambridge, UK.
| | - Ana-Teresa Maia
- Faculty of Medicine and Biomedical Sciences (FMCB), Universidade do Algarve, Faro, Portugal.
- Center for Research in Health Technologies and Information Systems (CINTESIS), Universidade do Algarve, Faro, Portugal.
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Liu Q, Chen L, Yin W, Nie Y, Zeng P, Yang X. Anti-tumor effect of ginkgetin on human hepatocellular carcinoma cell lines by inducing cell cycle arrest and promoting cell apoptosis. Cell Cycle 2021; 21:74-85. [PMID: 34878966 DOI: 10.1080/15384101.2021.1995684] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
This study explored the anti-tumor effect of ginkgetin, an extract from ginkgo biloba, on human hepatocellular carcinoma cell lines and the underlying mechanisms. Cell viability was measured by MTT assay. Apoptotic cell morphology was observed under an inverted microscope after Hoechst 33,258 staining, and the ratio of apoptotic and necrotic cells was examined by flow cytometry after FITC/PI staining. Cell cycle changes were analyzed using flow cytometry. Cytochrome c release and caspase 3 and 8 activities were monitored using the relevant reagent kits. The levels of cell cycle-related proteins were detected by Western blot. MTT results indicated that ginkgetin significantly reduced HepG2 cell viability in a dose-dependent manner. Cellular morphology observation revealed that ginkgetin induced typical apoptotic morphological features of HepG2 cells, such as increased apoptotic bodies and cell shrinkage. Cell cycle analysis showed that ginkgetin increased the proportion of cells in the S phase. S-phase cell accumulation could be attributed to the decreased expression of cell cycle regulatory factors. Similarly, ginkgetin also induced the apoptosis and S phase cell accumulation of another human HCC cell line SK-HEP-1. Furthermore, ginkgetin treatment increased caspase-3 activity and cytochrome c release but not caspase-8 activity, implying that ginkgetin might mediate cell apoptosis through the mitochondrial pathway. In addition, the tumor formation experiment in nude mice showed that ginkgetin administration inhibited tumor growth. These results suggest that ginkgetin could be a cell apoptosis stimulator by affecting the balance between cell proliferation and apoptosis, suggesting that ginkgetin might be suitable for human HCC treatment.
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Affiliation(s)
- Qiong Liu
- The First Affiliated Hospital, Department of Infectious Diseases, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Lingying Chen
- The First Affiliated Hospital, Department of blood transfusion, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Wenjun Yin
- The First Affiliated Hospital, Department of Clinical Laboratory, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Yuehua Nie
- The First Affiliated Hospital, Department of Radiation Oncology, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Penghui Zeng
- The First Affiliated Hospital, Department of Clinical Laboratory, Hengyang Medical School, University of South China, Hengyang, Hunan, China
| | - Xin Yang
- The First Affiliated Hospital, Department of Infectious Diseases, Hengyang Medical School, University of South China, Hengyang, Hunan, China
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Lian H, Guan P, Tan H, Zhang X, Meng Z. Near-infrared light triggered multi-hit therapeutic nanosystem for tumor specific photothermal effect amplified signal pathway regulation and ferroptosis. Bioact Mater 2021; 9:63-76. [PMID: 34820556 PMCID: PMC8586267 DOI: 10.1016/j.bioactmat.2021.07.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 06/30/2021] [Accepted: 07/15/2021] [Indexed: 02/08/2023] Open
Abstract
The high therapeutic resistance of tumor is the primary cause behind tumor recurrence and incurability. In recent years, scientists have devoted themselves to find a variety of treatments to solve this problem. Herein, we propose a multi-hit strategy that is based on the biodegradable hollow mesoporous Prussian blue (HMPB)-based nanosystem for tumor-specific therapy that encapsulated the critical heat shock protein 90 (HSP90) inhibitor 17-dimethylamino-ethylamino-17-demethoxydeldanamycin (17-DMAG). The nanosystem was further modified using thermotropic phase transition material star-PEG-PCL (sPP) and hyaluronic acid (HA), which offers near infrared light (NIR) responsive release characteristic, as well as enhanced tumor cell endocytosis. Upon cell internalization of 17-DMAG-HMPB@sPP@HA and under 808 nm laser irradiation, photothermal-conversion effect of HMPB directly kills cells using hyperthermia, which further causes phase transition of sPP to trigger release of 17-DMAG, inhibits HSP90 activity and blocks multiple signaling pathways, including cell cycle, Akt and HIF pathways. Additionally, the down-regulation of GPX4 protein expression by 17-DMAG and the release of ferric and ferrous ions from gradual degradation of HMPB in the endogenous mild acidic microenvironment in tumors promoted the occurrence of ferroptosis. Importantly, the antitumor effect of 17-DMAG and ferroptosis damage were amplified using photothermal effect of HMPB by accelerating release of ferric and ferrous ions, and reducing HSP90 expression in cells, which induced powerful antitumor effect in vitro and in vivo. This multi-hit therapeutic nanosystem helps provide a novel perspective for solving the predicament of cancer treatment, as well as a promising strategy for design of a novel cancer treatment nanoplatform. The tumor specific multi-hit therapeutic nanosystem was constructed. The nanosystem exerts anti-tumor effect includes photothermal effect, cell signaling pathway regulation and ferroptosis. The synergistic 17-DMAG-HMPB@sPP@HA nanosystem offers a promising strategy for effective tumor therapies.
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Affiliation(s)
- He Lian
- Department of Biomedical Engineering, School of Medical Instrumentation, Shenyang Pharmaceutical University, Shenyang, 110016, China
| | - Ping Guan
- School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, 110016, China
| | - Hongyan Tan
- School of Functional Food and Wine, Shenyang Pharmaceutical University, Shenyang, 110016, China
| | - Xiaoshu Zhang
- School of Functional Food and Wine, Shenyang Pharmaceutical University, Shenyang, 110016, China
| | - Zhaoxu Meng
- Department of Biomedical Engineering, School of Medical Instrumentation, Shenyang Pharmaceutical University, Shenyang, 110016, China
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Identification of candidate genes from androgenic gland in Macrobrachium nipponense regulated by eyestalk ablation. Sci Rep 2021; 11:19855. [PMID: 34615913 PMCID: PMC8494903 DOI: 10.1038/s41598-021-99022-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 09/17/2021] [Indexed: 11/28/2022] Open
Abstract
The eyestalk of crustaceans, such as Macrobrachium nipponense, contains many neurosecretory hormones affecting the process of reproduction, molting, metabolism of glucose, and other functions. In this study, important metabolic pathways and candidate genes involved in male sexual development were selected from M. nipponense. The methodology involved performing long-read and next generation transcriptome sequencing of genes from the androgenic gland after eyestalk ablation. qPCR analysis revealed that the mRNA expression of Mn-IAG was significantly increased after ablation of both the single-side (SS) and double-side (DS) eyestalk, compared with the control group (CG). The long-read transcriptome generated 49,840 non-redundant transcripts. A total of 1319, 2092 and 4351 differentially expressed genes (DEGs) were identified between CG versus SS, SS versus DS and CG versus DS, respectively. These data indicated that ablation of the double-sided eyestalk played stronger regulatory roles than the single-side ablation on male sexual development in M. nipponense. This was consistent with the qPCR analysis. Cell Cycle, Cellular Senescence, Oxidative Phosphorylation, Glycolysis/Gluconeogenesis and Steroid Hormone Biosynthesis were the primary enriched metabolic pathways in all three comparisons, and the important genes from these metabolic pathways were also selected. qPCR permitted secondary confirmation of ten DEGs identified through RNA-seq. RNAi-mediated silencing analyses of Hydroxysteroid dehydrogenase like 1 (HSDL1) revealed that HSDL1 has a positive regulatory effect on testes development. This study provides valuable insight into male sexual development in M. nipponense, including metabolic pathways and genes, paving the way for advanced studies on male sexual development in this species and in other crustaceans.
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Wei T, Grace M, Uberoi A, Romero-Masters JC, Lee D, Lambert PF, Munger K. The Mus musculus Papillomavirus Type 1 E7 Protein Binds to the Retinoblastoma Tumor Suppressor: Implications for Viral Pathogenesis. mBio 2021; 12:e0227721. [PMID: 34465025 PMCID: PMC8406179 DOI: 10.1128/mbio.02277-21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 08/05/2021] [Indexed: 12/17/2022] Open
Abstract
The species specificity of papillomaviruses has been a significant roadblock for performing in vivo pathogenesis studies in common model organisms. The Mus musculus papillomavirus type 1 (MmuPV1) causes cutaneous papillomas that can progress to squamous cell carcinomas in laboratory mice. The papillomavirus E6 and E7 genes encode proteins that establish and maintain a cellular milieu that allows for viral genome synthesis and viral progeny synthesis in growth-arrested, terminally differentiated keratinocytes. The E6 and E7 proteins provide this activity by binding to and functionally reprogramming key cellular regulatory proteins. The MmuPV1 E7 protein lacks the canonical LXCXE motif that mediates the binding of multiple viral oncoproteins to the cellular retinoblastoma tumor suppressor protein, RB1. Our proteomic experiments, however, revealed that MmuPV1 E7 still interacts with RB1. We show that MmuPV1 E7 interacts through its C terminus with the C-terminal domain of RB1. Binding of MmuPV1 E7 to RB1 did not cause significant activation of E2F-regulated cellular genes. MmuPV1 E7 expression was shown to be essential for papilloma formation. Experimental infection of mice with MmuPV1 expressing an E7 mutant that is defective for binding to RB1 caused delayed onset, lower incidence, and smaller sizes of papillomas. Our results demonstrate that the MmuPV1 E7 gene is essential and that targeting noncanonical activities of RB1, which are independent of RB1's ability to modulate the expression of E2F-regulated genes, contribute to papillomavirus-mediated pathogenesis. IMPORTANCE Papillomavirus infections cause a variety of epithelial hyperplastic lesions, or warts. While most warts are benign, some papillomaviruses cause lesions that can progress to squamous cell carcinomas, and approximately 5% of all human cancers are caused by human papillomavirus (HPV) infections. The papillomavirus E6 and E7 proteins are thought to function to reprogram host epithelial cells to enable viral genome replication in terminally differentiated, normally growth-arrested cells. E6 and E7 lack enzymatic activities and function by interacting and functionally altering host cell regulatory proteins. Many cellular proteins that can interact with E6 and E7 have been identified, but the biological relevance of these interactions for viral pathogenesis has not been determined. This is because papillomaviruses are species specific and do not infect heterologous hosts. Here, we use a recently established mouse papillomavirus (MmuPV1) model to investigate the role of the E7 protein in viral pathogenesis. We show that MmuPV1 E7 is necessary for papilloma formation. The retinoblastoma tumor suppressor protein (RB1) is targeted by many papillomaviral E7 proteins, including cancer-associated HPVs. We show that MmuPV1 E7 can bind RB1 and that infection with a mutant MmuPV1 virus that expresses an RB1 binding-defective E7 mutant caused smaller and fewer papillomas that arise with delayed kinetics.
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Affiliation(s)
- Tao Wei
- McArdle Laboratory for Cancer Research, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Miranda Grace
- Department of Developmental, Molecular and Chemical Biology, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - Aayushi Uberoi
- McArdle Laboratory for Cancer Research, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - James C. Romero-Masters
- McArdle Laboratory for Cancer Research, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Denis Lee
- McArdle Laboratory for Cancer Research, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Paul F. Lambert
- McArdle Laboratory for Cancer Research, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin, USA
| | - Karl Munger
- Department of Developmental, Molecular and Chemical Biology, Tufts University School of Medicine, Boston, Massachusetts, USA
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Tiwari A, Swamynathan S, Campbell G, Jhanji V, Swamynathan SK. BMP6 Regulates Corneal Epithelial Cell Stratification by Coordinating Their Proliferation and Differentiation and Is Upregulated in Pterygium. Invest Ophthalmol Vis Sci 2021; 61:46. [PMID: 32845956 PMCID: PMC7452852 DOI: 10.1167/iovs.61.10.46] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Purpose Proper balance between cell proliferation and differentiation is essential for corneal epithelial (CE) stratification and homeostasis. Although bone morphogenetic protein-6 (BMP6) is known to be expressed in the CE for over 25 years, its function in this tissue remains unknown. Here, we test the hypothesis that BMP6 promotes CE cell stratification and homeostasis by regulating their proliferation and differentiation. Methods We employed postnatal day-12 (PN-12), PN-14, PN-20, and PN-90 mouse eyes; human corneal limbal epithelial (HCLE) cells; and ocular surface fibrovascular disease pterygium tissues to evaluate the role of BMP6 in CE proliferation, differentiation, and pathology by RT-qPCR, immunoblots, and/or immunofluorescent staining. Cell proliferation was quantified by immunostaining for Ki67. Results Coincident with the mouse CE stratification between PN-12 and PN-20, BMP6 was significantly upregulated and the BMP6 antagonist Noggin downregulated. Mature CE retained high BMP6 and low Noggin expression at PN-90. BMP6 and its receptors BMPR1A and BMPR2 were upregulated during in vitro stratification of HCLE cells. Consistent with its anti-proliferative role, exogenous BMP6 suppressed HCLE cell proliferation, downregulated cyclin-D1 and cyclin-D2, and upregulated cell-cycle inhibitors Krüppel-like factor 4 (KLF4) and p21. BMP6 also upregulated the desmosomal cadherins desmoplakin and desmoglein in HCLE cells, consistent with its pro-differentiation role. Human pterygium displayed significant upregulation of BMP6 coupled with downregulation of Noggin and cell-cycle suppressors KLF4 and p21. Conclusions BMP6 coordinates CE stratification and homeostasis by regulating their proliferation and differentiation. BMP6 is significantly upregulated in human pterygium concurrent with downregulation of Noggin, KLF4, and p21.
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Affiliation(s)
- Anil Tiwari
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Sudha Swamynathan
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Gregory Campbell
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Vishal Jhanji
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States
| | - Shivalingappa K Swamynathan
- Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States.,Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States.,Fox Center for Vision Restoration, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States.,McGowan Institute of Regenerative Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
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10
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de la Cova CC, Townley R, Greenwald I. Negative feedback by conserved kinases patterns the degradation of Caenorhabditis elegans Raf in vulval fate patterning. Development 2020; 147:226094. [PMID: 33144396 DOI: 10.1242/dev.195941] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 10/27/2020] [Indexed: 11/20/2022]
Abstract
Activation of a canonical EGFR-Ras-Raf-ERK cascade initiates patterning of multipotent vulval precursor cells (VPCs) of Caenorhabditis elegans We have previously shown that this pathway includes a negative-feedback component in which MPK-1/ERK activity targets the upstream kinase LIN-45/Raf for degradation by the SEL-10/FBXW7 E3 ubiquitin ligase. This regulation requires a Cdc4 phosphodegron (CPD) in LIN-45 that is conserved in BRAF. Here, we identify and characterize the minimal degron that encompasses the CPD and is sufficient for SEL-10-mediated, MPK-1-dependent protein degradation. A targeted screen of conserved protein kinase-encoding genes yielded gsk-3 (an ortholog of human GSK3B) and cdk-2 (a CDK2-related kinase) as required for LIN-45 degron-mediated turnover. Genetic analysis revealed that LIN-45 degradation is blocked at the second larval stage due to cell cycle quiescence, and that relief of this block during the third larval stage relies on activation of CDKs. Additionally, activation of MPK-1 provides spatial pattern to LIN-45 degradation but does not bypass the requirement for gsk-3 and cdk-2 This analysis supports a model whereby MPK-1/ERK, GSK-3/GSK3 and CDK-2/CDK2, along with SEL-10/FBXW7, constitute a regulatory network that exerts spatial and temporal control of LIN-45/Raf degradation during VPC patterning.
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Affiliation(s)
- Claire C de la Cova
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA.,Department of Biological Sciences, University of Wisconsin Milwaukee, Milwaukee, WI 53201, USA
| | - Robert Townley
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA.,Department of Biological Sciences, University of Wisconsin Milwaukee, Milwaukee, WI 53201, USA
| | - Iva Greenwald
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
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11
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Urbach A, Witte OW. Divide or Commit - Revisiting the Role of Cell Cycle Regulators in Adult Hippocampal Neurogenesis. Front Cell Dev Biol 2019; 7:55. [PMID: 31069222 PMCID: PMC6491688 DOI: 10.3389/fcell.2019.00055] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Accepted: 03/28/2019] [Indexed: 12/21/2022] Open
Abstract
The adult dentate gyrus continuously generates new neurons that endow the brain with increased plasticity, helping to cope with changing environmental and cognitive demands. The process leading to the birth of new neurons spans several precursor stages and is the result of a coordinated series of fate decisions, which are tightly controlled by extrinsic signals. Many of these signals act through modulation of cell cycle (CC) components, not only to drive proliferation, but also for linage commitment and differentiation. In this review, we provide a comprehensive overview on key CC components and regulators, with emphasis on G1 phase, and analyze their specific functions in precursor cells of the adult hippocampus. We explore their role for balancing quiescence versus self-renewal, which is essential to maintain a lifelong pool of neural stem cells while producing new neurons “on demand.” Finally, we discuss available evidence and controversies on the impact of CC/G1 length on proliferation versus differentiation decisions.
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Affiliation(s)
- Anja Urbach
- Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
| | - Otto W Witte
- Hans Berger Department of Neurology, Jena University Hospital, Jena, Germany
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12
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Zhang J, Bu X, Wang H, Zhu Y, Geng Y, Nihira NT, Tan Y, Ci Y, Wu F, Dai X, Guo J, Huang YH, Fan C, Ren S, Sun Y, Freeman GJ, Sicinski P, Wei W. Cyclin D-CDK4 kinase destabilizes PD-L1 via cullin 3-SPOP to control cancer immune surveillance. Nature 2018; 553:91-95. [PMID: 29160310 PMCID: PMC5754234 DOI: 10.1038/nature25015] [Citation(s) in RCA: 667] [Impact Index Per Article: 111.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 11/08/2017] [Indexed: 02/07/2023]
Abstract
Treatments that target immune checkpoints, such as the one mediated by programmed cell death protein 1 (PD-1) and its ligand PD-L1, have been approved for treating human cancers with durable clinical benefit. However, many patients with cancer fail to respond to compounds that target the PD-1 and PD-L1 interaction, and the underlying mechanism(s) is not well understood. Recent studies revealed that response to PD-1-PD-L1 blockade might correlate with PD-L1 expression levels in tumour cells. Hence, it is important to understand the mechanistic pathways that control PD-L1 protein expression and stability, which can offer a molecular basis to improve the clinical response rate and efficacy of PD-1-PD-L1 blockade in patients with cancer. Here we show that PD-L1 protein abundance is regulated by cyclin D-CDK4 and the cullin 3-SPOP E3 ligase via proteasome-mediated degradation. Inhibition of CDK4 and CDK6 (hereafter CDK4/6) in vivo increases PD-L1 protein levels by impeding cyclin D-CDK4-mediated phosphorylation of speckle-type POZ protein (SPOP) and thereby promoting SPOP degradation by the anaphase-promoting complex activator FZR1. Loss-of-function mutations in SPOP compromise ubiquitination-mediated PD-L1 degradation, leading to increased PD-L1 levels and reduced numbers of tumour-infiltrating lymphocytes in mouse tumours and in primary human prostate cancer specimens. Notably, combining CDK4/6 inhibitor treatment with anti-PD-1 immunotherapy enhances tumour regression and markedly improves overall survival rates in mouse tumour models. Our study uncovers a novel molecular mechanism for regulating PD-L1 protein stability by a cell cycle kinase and reveals the potential for using combination treatment with CDK4/6 inhibitors and PD-1-PD-L1 immune checkpoint blockade to enhance therapeutic efficacy for human cancers.
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Affiliation(s)
- Jinfang Zhang
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Xia Bu
- Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Haizhen Wang
- Department of Cancer Biology, Dana-Farber Cancer Institute and Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Yasheng Zhu
- Department of Urology, Shanghai Changhai Hospital, Second Military Medical University, Shanghai 200433, P.R. China
| | - Yan Geng
- Department of Cancer Biology, Dana-Farber Cancer Institute and Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Naoe Taira Nihira
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Yuyong Tan
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
- Department of Gastroenterology, the Second Xiangya Hospital of Central South University, Changsha 410011, P.R. China
| | - Yanpeng Ci
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
- School of Life Science and Technology, Harbin Institute of Technology, Harbin, 150001, P.R. China
| | - Fei Wu
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
- Department of Urology, Huashan Hospital, Fudan University, Shanghai 200040, P.R. China
| | - Xiangpeng Dai
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Jianping Guo
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Yu-Han Huang
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Caoqi Fan
- Department of Cancer Biology, Dana-Farber Cancer Institute and Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, School of Life Sciences, Peking University, Beijing 100871, P.R. China
| | - Shancheng Ren
- Department of Urology, Shanghai Changhai Hospital, Second Military Medical University, Shanghai 200433, P.R. China
| | - Yinghao Sun
- Department of Urology, Shanghai Changhai Hospital, Second Military Medical University, Shanghai 200433, P.R. China
| | - Gordon J. Freeman
- Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Piotr Sicinski
- Department of Cancer Biology, Dana-Farber Cancer Institute and Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Wenyi Wei
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
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13
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Cytotoxicity of novel fluorinated alternatives to long-chain perfluoroalkyl substances to human liver cell line and their binding capacity to human liver fatty acid binding protein. Arch Toxicol 2017; 92:359-369. [PMID: 28864880 DOI: 10.1007/s00204-017-2055-1] [Citation(s) in RCA: 169] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 08/28/2017] [Indexed: 12/18/2022]
Abstract
Although shorter chain homologues and other types of fluorinated chemicals are currently used as alternatives to long-chain perfluoroalkyl substances (PFASs), their safety information remains unclear and urgently needed. Here, the cytotoxicity of several fluorinated alternatives (i.e., 6:2 fluorotelomer carboxylic acid (6:2 FTCA), 6:2 fluorotelomer sulfonic acid (6:2 FTSA), 6:2 chlorinated polyfluorinated ether sulfonate (6:2 Cl-PFESA), and hexafluoropropylene oxide (HFPO) homologues) to human liver HL-7702 cell line were measured and compared with perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). Their binding mode and affinity to human liver fatty acid binding protein (hL-FABP) were also determined. Compared with PFOA and PFOS, 6:2 Cl-PFESA, HFPO trimer acid (HFPO-TA), HFPO tetramer acid (HFPO-TeA), and 6:2 FTSA showed greater toxic effects on cell viabilities. At low exposure doses, these alternatives induced cell proliferation with similar mechanism which was different from that of PFOA and PFOS. Furthermore, binding affinity to hL-FABP decreased in the order of 6:2 FTCA < 6:2 FTSA < HFPO dimer acid (HFPO-DA) < PFOA < PFOS/6:2 Cl-PFESA/HFPO-TA. Due to their distinctive structure, 6:2 Cl-PFESA and HFPO homologues were bound to the hL-FABP inner pocket with unique binding modes and higher binding energy compared with PFOA and PFOS. This research enhances our understanding of the toxicity of PFAS alternatives during usage and provides useful evidence for the development of new alternatives.
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14
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Traynard P, Fauré A, Fages F, Thieffry D. Logical model specification aided by model-checking techniques: application to the mammalian cell cycle regulation. Bioinformatics 2017; 32:i772-i780. [PMID: 27587700 DOI: 10.1093/bioinformatics/btw457] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
MOTIVATION Understanding the temporal behaviour of biological regulatory networks requires the integration of molecular information into a formal model. However, the analysis of model dynamics faces a combinatorial explosion as the number of regulatory components and interactions increases. RESULTS We use model-checking techniques to verify sophisticated dynamical properties resulting from the model regulatory structure in the absence of kinetic assumption. We demonstrate the power of this approach by analysing a logical model of the molecular network controlling mammalian cell cycle. This approach enables a systematic analysis of model properties, the delineation of model limitations, and the assessment of various refinements and extensions based on recent experimental observations. The resulting logical model accounts for the main irreversible transitions between cell cycle phases, the sequential activation of cyclins, and the inhibitory role of Skp2, and further emphasizes the multifunctional role for the cell cycle inhibitor Rb. AVAILABILITY AND IMPLEMENTATION The original and revised mammalian cell cycle models are available in the model repository associated with the public modelling software GINsim (http://ginsim.org/node/189). CONTACT thieffry@ens.fr SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Pauline Traynard
- Computational Systems Biology Team, Institut de Biologie de L'Ecole Normale Supérieure (IBENS), CNRS, Inserm, Ecole Normale Supérieure, PSL Research University, Paris, France EPI Lifeware, Inria Inria Saclay Ile-de-France, Palaiseau, France
| | - Adrien Fauré
- Graduate School of Science and Engineering, Yamaguchi University, Yamaguchi, Japan
| | - François Fages
- EPI Lifeware, Inria Inria Saclay Ile-de-France, Palaiseau, France
| | - Denis Thieffry
- Computational Systems Biology Team, Institut de Biologie de L'Ecole Normale Supérieure (IBENS), CNRS, Inserm, Ecole Normale Supérieure, PSL Research University, Paris, France EPI Lifeware, Inria Inria Saclay Ile-de-France, Palaiseau, France
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15
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Zhang H, Cui R, Guo X, Hu J, Dai J. Low dose perfluorooctanoate exposure promotes cell proliferation in a human non-tumor liver cell line. JOURNAL OF HAZARDOUS MATERIALS 2016; 313:18-28. [PMID: 27045622 DOI: 10.1016/j.jhazmat.2016.03.077] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 03/25/2016] [Accepted: 03/27/2016] [Indexed: 05/27/2023]
Abstract
Perfluorooctanoate (PFOA) is a well-known persistent organic pollutant widely found in the environment, wildlife and humans. Medical surveillance and experimental studies have investigated the potential effects of PFOA on human livers, but the hepatotoxicity of PFOA on humans and its underlying mechanism remain to be clarified. We exposed a human liver cell line (HL-7702) to 50μM PFOA for 48h and 96h, and identified 111 significantly differentially expressed proteins by iTRAQ analysis. A total of 46 proteins were related to cell proliferation and apoptosis. Through further analysis of the cell cycle, apoptosis and their related proteins, we found that low doses of PFOA (50-100μM) promoted cell proliferation and numbers by promoting cells from the G1 to S phases, whereas high doses of PFOA (200-400μM) led to reduced HL-7702 cell numbers compared with that of the control mainly due to cell cycle arrest in the G0/G1 phase. To our knowledge, this is the first report on the promotion of cell cycle progression in human cells following PFOA exposure.
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Affiliation(s)
- Hongxia Zhang
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Ruina Cui
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Xuejiang Guo
- State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 210029, PR China
| | - Jiayue Hu
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Jiayin Dai
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China.
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16
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Fan YC, Cui CC, Zhu YS, Zhang L, Shi M, Yu JS, Bai J, Zheng JN. Overexpression of CAP1 and its significance in tumor cell proliferation, migration and invasion in glioma. Oncol Rep 2016; 36:1619-25. [PMID: 27432289 DOI: 10.3892/or.2016.4936] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 04/19/2016] [Indexed: 11/06/2022] Open
Abstract
Adenylate cyclase-associated protein 1 (CAP1), a protein related to the regulation of actin filaments and the Ras/cAMP pathway, is associated with tumor progression. Nevertheless, the expression level and effects of CAP1 in regards to glioma have not been reported. In the present study, we examined the expression of CAP1 in glioma and tumor adjacent normal brain tissues by tissue microarray and immunohistochemistry. Our results showed that CAP1 was overexpressed in glioma tissues in comparison with that noted in the tumor adjacent normal brain tissues and increased staining of CAP1 was found to be correlated with WHO stage. In addition, we discovered that knockdown of CAP1 by specific RNA interference markedly inhibited cell growth and caused downregulation of the proliferation markers, PCNA and cyclin A. We further demonstrated that knockdown of CAP1 inhibited cell metastatic abilities by downregulating N-cadherin and vimentin and upregulating E-cadherin. These findings revealed that CAP1 expression is markedly increased in human glioma and that downregulation of CAP1 in tumors may serve as a treatment for glioma patients.
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Affiliation(s)
- Yue-Chao Fan
- Department of Neurosurgery, The Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
| | - Chen-Chen Cui
- Department of Neurosurgery, The Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
| | - Yi-Shuo Zhu
- Department of Neurosurgery, The Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
| | - Lei Zhang
- Department of Neurosurgery, The Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
| | - Meng Shi
- Department of Neurosurgery, The Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
| | - Jin-Song Yu
- Department of Neurosurgery, The Affiliated Hospital of Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
| | - Jin Bai
- Jiangsu Key Laboratory of Biological Cancer Therapy, Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
| | - Jun-Nian Zheng
- Jiangsu Key Laboratory of Biological Cancer Therapy, Xuzhou Medical College, Xuzhou, Jiangsu 221002, P.R. China
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17
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Abstract
Uncontrolled cellular proliferation, mediated by dysregulation of the cell-cycle machinery and activation of cyclin-dependent kinases (CDKs) to promote cell-cycle progression, lies at the heart of cancer as a pathological process. Clinical implementation of first-generation, nonselective CDK inhibitors, designed to inhibit this proliferation, was originally hampered by the high risk of toxicity and lack of efficacy noted with these agents. The emergence of a new generation of selective CDK4/6 inhibitors, including ribociclib, abemaciclib and palbociclib, has enabled tumour types in which CDK4/6 has a pivotal role in the G1-to-S-phase cell-cycle transition to be targeted with improved effectiveness, and fewer adverse effects. Results of pivotal phase III trials investigating palbociclib in patients with advanced-stage oestrogen receptor (ER)-positive breast cancer have demonstrated a substantial improvement in progression-free survival, with a well-tolerated toxicity profile. Mechanisms of acquired resistance to CDK4/6 inhibitors are beginning to emerge that, although unwelcome, might enable rational post-CDK4/6 inhibitor therapeutic strategies to be identified. Extending the use of CDK4/6 inhibitors beyond ER-positive breast cancer is challenging, and will likely require biomarkers that are predictive of a response, and the use of combination therapies in order to optimize CDK4/6 targeting.
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Affiliation(s)
- Ben O'Leary
- The Breakthrough Breast Cancer Research Centre, The Institute of Cancer Research, Fulham Road, London SW3 6JB, UK
| | - Richard S Finn
- Division of Haematology/Oncology, Geffen School of Medicine at UCLA, Los Angeles, California 90095, USA
| | - Nicholas C Turner
- The Breakthrough Breast Cancer Research Centre, The Institute of Cancer Research, Fulham Road, London SW3 6JB, UK.,Breast Unit, Royal Marsden Hospital, Fulham Road, London SW3 6JJ, UK
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18
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Camarillo JM, Rose KL, Galligan JJ, Xu S, Marnett LJ. Covalent Modification of CDK2 by 4-Hydroxynonenal as a Mechanism of Inhibition of Cell Cycle Progression. Chem Res Toxicol 2016; 29:323-32. [PMID: 26910110 DOI: 10.1021/acs.chemrestox.5b00485] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Oxidative stress is a contributing factor in a number of chronic diseases, including cancer, atherosclerosis, and neurodegenerative diseases. Lipid peroxidation that occurs during periods of oxidative stress results in the formation of lipid electrophiles, which can modify a multitude of proteins in the cell. 4-Hydroxy-2-nonenal (HNE) is one of the most well-studied lipid electrophiles and has previously been shown to arrest cells at the G1/S transition. Recently, proteomic data have shown that HNE is capable of covalently modifying CDK2, the kinase responsible for the G1/S transition. Here, we identify the sites adducted by HNE using recombinant CDK2 and show that HNE treatment suppresses the kinase activity of the enzyme. We further identify sites of adduction in HNE-treated intact human colorectal carcinoma cells (RKO) and show that HNE-dependent modification in cells is long-lived, disrupts CDK2 function, and correlates with a delay of progression of the cells into S-phase. We propose that adduction of CDK2 by HNE directly alters its activity, contributing to the cell cycle delay.
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Affiliation(s)
- Jeannie M Camarillo
- A.B. Hancock Jr. Memorial Laboratory for Cancer Research, Departments of Biochemistry, §Chemistry, and #Pharmacology, ‡Mass Spectrometry Research Center, ⊥Vanderbilt Institute of Chemical Biology, Center in Molecular Toxicology, Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine , Nashville, Tennessee 37232-0146, United States
| | - Kristie L Rose
- A.B. Hancock Jr. Memorial Laboratory for Cancer Research, Departments of Biochemistry, §Chemistry, and #Pharmacology, ‡Mass Spectrometry Research Center, ⊥Vanderbilt Institute of Chemical Biology, Center in Molecular Toxicology, Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine , Nashville, Tennessee 37232-0146, United States
| | - James J Galligan
- A.B. Hancock Jr. Memorial Laboratory for Cancer Research, Departments of Biochemistry, §Chemistry, and #Pharmacology, ‡Mass Spectrometry Research Center, ⊥Vanderbilt Institute of Chemical Biology, Center in Molecular Toxicology, Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine , Nashville, Tennessee 37232-0146, United States
| | - Shu Xu
- A.B. Hancock Jr. Memorial Laboratory for Cancer Research, Departments of Biochemistry, §Chemistry, and #Pharmacology, ‡Mass Spectrometry Research Center, ⊥Vanderbilt Institute of Chemical Biology, Center in Molecular Toxicology, Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine , Nashville, Tennessee 37232-0146, United States
| | - Lawrence J Marnett
- A.B. Hancock Jr. Memorial Laboratory for Cancer Research, Departments of Biochemistry, §Chemistry, and #Pharmacology, ‡Mass Spectrometry Research Center, ⊥Vanderbilt Institute of Chemical Biology, Center in Molecular Toxicology, Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine , Nashville, Tennessee 37232-0146, United States
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19
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Cui R, Zhang H, Guo X, Cui Q, Wang J, Dai J. Proteomic analysis of cell proliferation in a human hepatic cell line (HL-7702) induced by perfluorooctane sulfonate using iTRAQ. JOURNAL OF HAZARDOUS MATERIALS 2015; 299:361-370. [PMID: 26143199 DOI: 10.1016/j.jhazmat.2015.06.031] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 06/08/2015] [Accepted: 06/18/2015] [Indexed: 06/04/2023]
Abstract
Perfluorooctane sulfonate (PFOS) is a commonly used and widely distributed perfluorinated compound proven to cause adverse health outcomes. However, how PFOS affects liver cell proliferation is not well understood. In this experiment, we exposed a human liver cell line (HL-7702) to 50 μM PFOS for 48 h and 96 h. We identified 52 differentially expressed proteins using a quantitative proteomic approach. Among them, 27 were associated with cell proliferation, including hepatoma-derived growth factor (Hdgf) and proliferation biomarkers Mk167 (Ki67) and Top2α. Results from MTT, cell counting, and cell cycle analysis showed low-dose PFOS (<200 μM) stimulated HL-7702 cell viability at 48 h and 96 h, reduced the G0/G1 percentage, and increased the S+G2/M percentage. Moreover, levels of Cyclin D1, Cyclin E2, Cyclin A2, Cyclin B1 and their partner Cdks were elevated, and the expression of regulating proteins like c-Myc, p53, p21 waf/cip1 and Myt1, as well as the phosphorylation levels of p-Wee1(S642), p-Chk1(S345) and p-Chk2(T68), were disturbed. We hypothesized that low-dose PFOS stimulated HL-7702 proliferation by driving cells into G1 through elevating cyclins/cdks expression, and by promoting cell cycle progression through altering other regulating proteins. This research will shed light on the mechanisms behind PFOS-mediated human hepatotoxicity.
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Affiliation(s)
- Ruina Cui
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Hongxia Zhang
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Xuejiang Guo
- State Key Laboratory of Reproductive Medicine, Department of Histology and Embryology, Nanjing Medical University, Nanjing 210029, PR China
| | - Qianqian Cui
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Jianshe Wang
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China
| | - Jiayin Dai
- Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, PR China.
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20
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Benavente CA, Dyer MA. Genetically engineered mouse and orthotopic human tumor xenograft models of retinoblastoma. Methods Mol Biol 2015; 1267:307-17. [PMID: 25636476 DOI: 10.1007/978-1-4939-2297-0_15] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Retinoblastoma is a rare pediatric cancer of the developing retina that initiates with biallelic inactivation of the RB1 gene. Murine models of retinoblastoma provide excellent tools for preclinical studies as well as for the study of the biological processes that drive tumorigenesis following Rb loss. In this chapter, we describe several genetically engineered mouse and orthotopic human xenograft models of retinoblastoma and discuss the advantages and disadvantages of these models.
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Affiliation(s)
- Claudia A Benavente
- Department of Chemical Biology and Therapeutics, St. Jude Children's Research Hospital, Memphis, TN, 38105-3678, USA
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21
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Wiedemeyer WR, Beach JA, Karlan BY. Reversing Platinum Resistance in High-Grade Serous Ovarian Carcinoma: Targeting BRCA and the Homologous Recombination System. Front Oncol 2014. [PMID: 24624361 DOI: 10.3389/fonc.2014.00034]+[] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Resistance to platinum chemotherapy is one of the main factors driving ovarian cancer mortality, and overcoming platinum resistance is considered one of the greatest challenges in ovarian cancer research. Genetic and functional evidence points to the homologous recombination (HR) DNA repair system, and BRCA1 and BRCA2 in particular, as main determinants of response to platinum therapy. BRCA-mutant ovarian cancers are especially sensitive to platinum, associated with better survival, and amenable to poly ADP ribose polymerase inhibitor treatment. Here, we discuss a therapeutic concept that seeks to disrupt HR capacity via targeting of BRCA1 and BRCA2 functionality in order to reverse platinum resistance in BRCA-proficient high-grade serous ovarian cancers (HGSOC). We review the molecular signaling pathways that converge on BRCA1 and BRCA2, their activation status in ovarian cancer, and therapeutic options to modulate BRCA function. Several recent publications demonstrate efficient chemosensitization of BRCA-proficient cancers by combining targeted therapy with standard platinum-based agents. Due to its inherent genomic heterogeneity, molecularly defined subgroups of HGSOC may require different approaches. We seek to provide an overview of available agents and their potential use to reverse platinum resistance by inhibiting the HR system, either directly or indirectly, by targeting oncogenic activators of HR.
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Affiliation(s)
- W Ruprecht Wiedemeyer
- Women's Cancer Program, Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center , Los Angeles, CA , USA ; Department of Obstetrics and Gynecology, David Geffen School of Medicine, University of California Los Angeles , Los Angeles, CA , USA
| | - Jessica A Beach
- Women's Cancer Program, Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center , Los Angeles, CA , USA ; Graduate Program in Biomedical Sciences and Translational Medicine, Cedars-Sinai Medical Center , Los Angeles, CA , USA
| | - Beth Y Karlan
- Women's Cancer Program, Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center , Los Angeles, CA , USA ; Department of Obstetrics and Gynecology, David Geffen School of Medicine, University of California Los Angeles , Los Angeles, CA , USA
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Wiedemeyer WR, Beach JA, Karlan BY. Reversing Platinum Resistance in High-Grade Serous Ovarian Carcinoma: Targeting BRCA and the Homologous Recombination System. Front Oncol 2014. [PMID: 24624361 DOI: 10.3389/fonc.2014.00034] [] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Resistance to platinum chemotherapy is one of the main factors driving ovarian cancer mortality, and overcoming platinum resistance is considered one of the greatest challenges in ovarian cancer research. Genetic and functional evidence points to the homologous recombination (HR) DNA repair system, and BRCA1 and BRCA2 in particular, as main determinants of response to platinum therapy. BRCA-mutant ovarian cancers are especially sensitive to platinum, associated with better survival, and amenable to poly ADP ribose polymerase inhibitor treatment. Here, we discuss a therapeutic concept that seeks to disrupt HR capacity via targeting of BRCA1 and BRCA2 functionality in order to reverse platinum resistance in BRCA-proficient high-grade serous ovarian cancers (HGSOC). We review the molecular signaling pathways that converge on BRCA1 and BRCA2, their activation status in ovarian cancer, and therapeutic options to modulate BRCA function. Several recent publications demonstrate efficient chemosensitization of BRCA-proficient cancers by combining targeted therapy with standard platinum-based agents. Due to its inherent genomic heterogeneity, molecularly defined subgroups of HGSOC may require different approaches. We seek to provide an overview of available agents and their potential use to reverse platinum resistance by inhibiting the HR system, either directly or indirectly, by targeting oncogenic activators of HR.
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Affiliation(s)
- W Ruprecht Wiedemeyer
- Women's Cancer Program, Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center , Los Angeles, CA , USA ; Department of Obstetrics and Gynecology, David Geffen School of Medicine, University of California Los Angeles , Los Angeles, CA , USA
| | - Jessica A Beach
- Women's Cancer Program, Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center , Los Angeles, CA , USA ; Graduate Program in Biomedical Sciences and Translational Medicine, Cedars-Sinai Medical Center , Los Angeles, CA , USA
| | - Beth Y Karlan
- Women's Cancer Program, Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center , Los Angeles, CA , USA ; Department of Obstetrics and Gynecology, David Geffen School of Medicine, University of California Los Angeles , Los Angeles, CA , USA
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Wiedemeyer WR, Beach JA, Karlan BY. Reversing Platinum Resistance in High-Grade Serous Ovarian Carcinoma: Targeting BRCA and the Homologous Recombination System. Front Oncol 2014; 4:34. [PMID: 24624361 PMCID: PMC3939430 DOI: 10.3389/fonc.2014.00034] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 02/11/2014] [Indexed: 11/26/2022] Open
Abstract
Resistance to platinum chemotherapy is one of the main factors driving ovarian cancer mortality, and overcoming platinum resistance is considered one of the greatest challenges in ovarian cancer research. Genetic and functional evidence points to the homologous recombination (HR) DNA repair system, and BRCA1 and BRCA2 in particular, as main determinants of response to platinum therapy. BRCA-mutant ovarian cancers are especially sensitive to platinum, associated with better survival, and amenable to poly ADP ribose polymerase inhibitor treatment. Here, we discuss a therapeutic concept that seeks to disrupt HR capacity via targeting of BRCA1 and BRCA2 functionality in order to reverse platinum resistance in BRCA-proficient high-grade serous ovarian cancers (HGSOC). We review the molecular signaling pathways that converge on BRCA1 and BRCA2, their activation status in ovarian cancer, and therapeutic options to modulate BRCA function. Several recent publications demonstrate efficient chemosensitization of BRCA-proficient cancers by combining targeted therapy with standard platinum-based agents. Due to its inherent genomic heterogeneity, molecularly defined subgroups of HGSOC may require different approaches. We seek to provide an overview of available agents and their potential use to reverse platinum resistance by inhibiting the HR system, either directly or indirectly, by targeting oncogenic activators of HR.
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Affiliation(s)
- W Ruprecht Wiedemeyer
- Women's Cancer Program, Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center , Los Angeles, CA , USA ; Department of Obstetrics and Gynecology, David Geffen School of Medicine, University of California Los Angeles , Los Angeles, CA , USA
| | - Jessica A Beach
- Women's Cancer Program, Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center , Los Angeles, CA , USA ; Graduate Program in Biomedical Sciences and Translational Medicine, Cedars-Sinai Medical Center , Los Angeles, CA , USA
| | - Beth Y Karlan
- Women's Cancer Program, Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center , Los Angeles, CA , USA ; Department of Obstetrics and Gynecology, David Geffen School of Medicine, University of California Los Angeles , Los Angeles, CA , USA
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Siriwardana G, Seligman PA. Two cell cycle blocks caused by iron chelation of neuroblastoma cells: separating cell cycle events associated with each block. Physiol Rep 2013; 1:e00176. [PMID: 24744856 PMCID: PMC3970748 DOI: 10.1002/phy2.176] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 11/04/2013] [Accepted: 11/06/2013] [Indexed: 12/14/2022] Open
Abstract
Studies have presented evidence that besides the well described S phase block, treatment of cancer cell lines with the iron chelator deferrioxamine (DFO) also results in an earlier block in G1 phase. In this article, measurements of cell cycle regulatory proteins define this block at a very specific point in G1. DFO treatment results in markedly decreased cyclin A protein levels. Cyclin E levels that accumulate in early to mid‐G1 are increased in cells treated with DFO as compared to the resting cells. The DFO S phase block is shown after cells are arrested at G1/S by (aphidicolin) then released into DFO. The same S phase block occurs with DFO treatment of a neuroblastoma cell line relatively resistant to the G1 DFO block. These experiments clearly differentiate the S phase DFO block from the earlier block pinpointed to a point in mid‐G1, before G1/S when cyclin E protein increases but before increased cyclin A synthesis. Apoptosis was observed in cells inhibited by DFO at both cell cycle arrest points. Iron chelation inhibits cell proliferation at two phases in the cell cycle. The block in G1 phase is now separated from the block in S phase by specific differences in expression of cell cycle regulatory events.
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Affiliation(s)
- Gamini Siriwardana
- Division of Hematology, Hematologic Malignancies and Stem Cell Transplantation, University of Colorado School of Medicine, 12700 E. 19th Avenue, Room 9122RC 2, MS B170, Aurora, 80045, Colorado
| | - Paul A Seligman
- Division of Hematology, Hematologic Malignancies and Stem Cell Transplantation, University of Colorado School of Medicine, 12700 E. 19th Avenue, Room 9122RC 2, MS B170, Aurora, 80045, Colorado
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Yang L, Meng Y, Bao C, Liu W, Ma C, Li A, Xuan Z, Shan G, Jia Y. Robustness and backbone motif of a cancer network regulated by miR-17-92 cluster during the G1/S transition. PLoS One 2013; 8:e57009. [PMID: 23469179 PMCID: PMC3585929 DOI: 10.1371/journal.pone.0057009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Accepted: 01/16/2013] [Indexed: 11/18/2022] Open
Abstract
Based on interactions among transcription factors, oncogenes, tumor suppressors and microRNAs, a Boolean model of cancer network regulated by miR-17-92 cluster is constructed, and the network is associated with the control of G1/S transition in the mammalian cell cycle. The robustness properties of this regulatory network are investigated by virtue of the Boolean network theory. It is found that, during G1/S transition in the cell cycle process, the regulatory networks are robustly constructed, and the robustness property is largely preserved with respect to small perturbations to the network. By using the unique process-based approach, the structure of this network is analyzed. It is shown that the network can be decomposed into a backbone motif which provides the main biological functions, and a remaining motif which makes the regulatory system more stable. The critical role of miR-17-92 in suppressing the G1/S cell cycle checkpoint and increasing the uncontrolled proliferation of the cancer cells by targeting a genetic network of interacting proteins is displayed with our model.
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Affiliation(s)
- Lijian Yang
- Institute of Biophysics and Department of Physics, Central China Normal University, Wuhan, China
| | - Yan Meng
- Institute of Biophysics and Department of Physics, Central China Normal University, Wuhan, China
| | - Chun Bao
- Institute of Biophysics and Department of Physics, Central China Normal University, Wuhan, China
- School of Life Sciences, University of Science and Technology of China, Hefei, China
| | - Wangheng Liu
- Institute of Biophysics and Department of Physics, Central China Normal University, Wuhan, China
| | - Chengzhang Ma
- Institute of Biophysics and Department of Physics, Central China Normal University, Wuhan, China
| | - Anbang Li
- Institute of Biophysics and Department of Physics, Central China Normal University, Wuhan, China
| | - Zhan Xuan
- Institute of Biophysics and Department of Physics, Central China Normal University, Wuhan, China
| | - Ge Shan
- School of Life Sciences, University of Science and Technology of China, Hefei, China
- * E-mail: (YJ); (GS)
| | - Ya Jia
- Institute of Biophysics and Department of Physics, Central China Normal University, Wuhan, China
- * E-mail: (YJ); (GS)
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26
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Zhang X, Bai Q, Xu L, Kakiyama G, Pandak WM, Zhang Z, Ren S. Cytosolic sulfotransferase 2B1b promotes hepatocyte proliferation gene expression in vivo and in vitro. Am J Physiol Gastrointest Liver Physiol 2012; 303:G344-55. [PMID: 22679001 PMCID: PMC3423104 DOI: 10.1152/ajpgi.00403.2011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Cytosolic sulfotransferase 2B1b (SULT2B1b) catalyzes the sulfation of 3β-hydroxysteroids and functions as a selective cholesterol and oxysterol sulfotransferase. Activation of liver X receptors (LXRs) by oxysterols has been known to be an antiproliferative factor. Overexpression of SULT2B1b impairs LXR's response to oxysterols, by which it regulates lipid metabolism. The aim of this study was to investigate in vivo and in vitro effects of SULT2B1b on liver proliferation and the underlying mechanisms. Primary rat hepatocytes and C57BL/6 mice were infected with adenovirus encoding SULT2B1b. Liver proliferation was determined by measuring the proliferating cell nuclear antigen (PCNA) immunostaining labeling index. The correlation between SULT2B1b and PCNA expression in mouse liver tissues was determined by double immunofluorescence. Gene expressions were evaluated by quantitative real-time PCR and Western blot analysis. SULT2B1b overexpression in mouse liver tissues increased PCNA-positive cells in a dose- and time-dependent manner. The increased expression of PCNA in mouse liver tissues was only observed in the SULT2B1b transgenic cells. Small interference RNA SULT2B1b significantly inhibited cell cycle regulatory gene expressions in primary rat hepatocytes. LXR activation by T0901317 effectively suppressed SULT2B1b-induced gene expression in vivo and in vitro. SULT2B1b may promote hepatocyte proliferation by inactivating oxysterol/LXR signaling.
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Affiliation(s)
- Xin Zhang
- 1Department of Pathology, Fudan University Shanghai Medical College, Shanghai, China; and ,2Department of Medicine, Virginia Commonwealth University/Veterans Affairs McGuire Medical Center, Richmond, Virginia
| | - Qianming Bai
- 1Department of Pathology, Fudan University Shanghai Medical College, Shanghai, China; and ,2Department of Medicine, Virginia Commonwealth University/Veterans Affairs McGuire Medical Center, Richmond, Virginia
| | - Leyuan Xu
- 2Department of Medicine, Virginia Commonwealth University/Veterans Affairs McGuire Medical Center, Richmond, Virginia
| | - Genta Kakiyama
- 2Department of Medicine, Virginia Commonwealth University/Veterans Affairs McGuire Medical Center, Richmond, Virginia
| | - William M. Pandak
- 2Department of Medicine, Virginia Commonwealth University/Veterans Affairs McGuire Medical Center, Richmond, Virginia
| | - Zhigang Zhang
- 1Department of Pathology, Fudan University Shanghai Medical College, Shanghai, China; and
| | - Shunlin Ren
- 2Department of Medicine, Virginia Commonwealth University/Veterans Affairs McGuire Medical Center, Richmond, Virginia
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27
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Honda A, Valogne Y, Bou Nader M, Bréchot C, Faivre J. An intron-retaining splice variant of human cyclin A2, expressed in adult differentiated tissues, induces a G1/S cell cycle arrest in vitro. PLoS One 2012; 7:e39249. [PMID: 22745723 PMCID: PMC3379989 DOI: 10.1371/journal.pone.0039249] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Accepted: 05/21/2012] [Indexed: 11/18/2022] Open
Abstract
Background Human cyclin A2 is a key regulator of S phase progression and entry into mitosis. Alternative splice variants of the G1 and mitotic cyclins have been shown to interfere with full-length cyclin functions to modulate cell cycle progression and are therefore likely to play a role in differentiation or oncogenesis. The alternative splicing of human cyclin A2 has not yet been studied. Methodology/Principal Findings Sequence-specific primers were designed to amplify various exon–intron regions of cyclin A2 mRNA in cell lines and human tissues. Intron retaining PCR products were cloned and sequenced and then overexpressed in HeLa cells. The subcellular localization of the splice variants was studied using confocal and time-lapse microscopy, and their impact on the cell cycle by flow cytometry, immunoblotting and histone H1 kinase activity. We found a splice variant of cyclin A2 mRNA called A2V6 that partly retains Intron 6. The gene expression pattern of A2V6 mRNA in human tissues was noticeably different from that of wild-type cyclin A2 (A2WT) mRNA. It was lower in proliferating fetal tissues and stronger in some differentiated adult tissues, especially, heart. In transfected HeLa cells, A2V6 localized exclusively in the cytoplasm whereas A2WT accumulated in the nucleus. We show that A2V6 induced a clear G1/S cell cycle arrest associated with a p21 and p27 upregulation and an inhibition of retinoblastoma protein phosphorylation. Like A2WT, A2V6 bound CDK2, but the A2V6/CDK2 complex did not phosphorylate histone H1. Conclusion/Significance This study has revealed that some highly differentiated human tissues express an intron-retaining cyclin A2 mRNA that induced a G1/S block in vitro. Contrary to full-length cyclin A2, which regulates cell proliferation, the A2V6 splice variant might play a role in regulating nondividing cell states such as terminal differentiation or senescence.
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Affiliation(s)
- Arata Honda
- Tokyo Metropolitan Health and Medical Treatment Corporation, Ebara Hospital, Tokyo, Japan
- INSERM, U785, Centre Hépatobiliaire, Villejuif, France
- Université Paris-Sud, Faculté de Médecine, Villejuif, France
| | - Yannick Valogne
- INSERM, U785, Centre Hépatobiliaire, Villejuif, France
- Université Paris-Sud, Faculté de Médecine, Villejuif, France
| | - Myriam Bou Nader
- INSERM, U785, Centre Hépatobiliaire, Villejuif, France
- Université Paris-Sud, Faculté de Médecine, Villejuif, France
| | - Christian Bréchot
- INSERM, U785, Centre Hépatobiliaire, Villejuif, France
- Université Paris-Sud, Faculté de Médecine, Villejuif, France
| | - Jamila Faivre
- INSERM, U785, Centre Hépatobiliaire, Villejuif, France
- Université Paris-Sud, Faculté de Médecine, Villejuif, France
- * E-mail:
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28
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Siu KT, Rosner MR, Minella AC. An integrated view of cyclin E function and regulation. Cell Cycle 2012; 11:57-64. [PMID: 22186781 DOI: 10.4161/cc.11.1.18775] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Cancers of diverse cell lineages express high levels of cyclin E, and in various studies, cyclin E overexpression correlates with increased tumor aggression. One way that normal control of cyclin E expression is disabled in cancer cells is via loss-of-function mutations sustained by FBXW7. This gene encodes the Fbw7 tumor suppressor protein that provides substrate specificity for a ubiquitin ligase complex that targets multiple oncoproteins for degradation. Numerous other mechanisms besides Fbw7 mutations can deregulate cyclin E expression and activity in cancer cells. Recent reports demonstrate that inappropriate cyclin E expression may have far-reaching biological consequences for cell physiology, including altering gene expression programs governing proliferation, differentiation, survival and senescence. In this review, we discuss the function of mammalian cyclin E in the context of these new data as well as the complex network that connects cyclin E functions to the cellular controls regulating its expression and activity.
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Affiliation(s)
- Ka Tat Siu
- Department of Medicine, Hematology/Oncology Division, Integrated Graduate Program in the Life Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
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29
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Pagliuca FW, Collins MO, Lichawska A, Zegerman P, Choudhary JS, Pines J. Quantitative proteomics reveals the basis for the biochemical specificity of the cell-cycle machinery. Mol Cell 2011; 43:406-17. [PMID: 21816347 PMCID: PMC3332305 DOI: 10.1016/j.molcel.2011.05.031] [Citation(s) in RCA: 115] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Revised: 04/06/2011] [Accepted: 05/13/2011] [Indexed: 01/06/2023]
Abstract
Cyclin-dependent kinases comprise the conserved machinery that drives progress through the cell cycle, but how they do this in mammalian cells is still unclear. To identify the mechanisms by which cyclin-cdks control the cell cycle, we performed a time-resolved analysis of the in vivo interactors of cyclins E1, A2, and B1 by quantitative mass spectrometry. This global analysis of context-dependent protein interactions reveals the temporal dynamics of cyclin function in which networks of cyclin-cdk interactions vary according to the type of cyclin and cell-cycle stage. Our results explain the temporal specificity of the cell-cycle machinery, thereby providing a biochemical mechanism for the genetic requirement for multiple cyclins in vivo and reveal how the actions of specific cyclins are coordinated to control the cell cycle. Furthermore, we identify key substrates (Wee1 and c15orf42/Sld3) that reveal how cyclin A is able to promote both DNA replication and mitosis.
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30
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In vivo efficacy of photodynamic therapy in three new xenograft models of human retinoblastoma. Photodiagnosis Photodyn Ther 2010; 7:275-83. [DOI: 10.1016/j.pdpdt.2010.09.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Revised: 09/07/2010] [Accepted: 09/15/2010] [Indexed: 11/20/2022]
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Baydoun HH, Pancewicz J, Bai X, Nicot C. HTLV-I p30 inhibits multiple S phase entry checkpoints, decreases cyclin E-CDK2 interactions and delays cell cycle progression. Mol Cancer 2010; 9:302. [PMID: 21092281 PMCID: PMC3000403 DOI: 10.1186/1476-4598-9-302] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2010] [Accepted: 11/23/2010] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Human T-cell leukemia virus type I (HTLV-I) has efficiently adapted to its host and establishes a persistent infection characterized by low levels of viral gene expression and slow proliferation of HTLV-I infected cells over decades. We have previously found that HTLV-I p30 is a negative regulator of virus expression. RESULTS In this study we show that p30 targets multiple cell cycle checkpoints resulting in a delayed entry into S phase. We found that p30 binds to cyclin E and CDK2 and prevents the formation of active cyclin E-CDK2 complexes. In turn, this decreases the phosphorylation levels of Rb and prevents the release of E2F and its transcriptional activation of genes required for G1/S transition. Our studies also show that HTLV-II p28 does not bind cyclin E and does not affect cell cycle progression. CONCLUSIONS In contrast to HTLV-I, the HTLV-II-related retrovirus is not oncogenic in humans. Here we report that the HTLV-I p30 delays cell cycle progression while its homologue, HTLV-II p28, does not, providing evidence for important differences between these two related retrovirus proteins.
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Affiliation(s)
- Hicham H Baydoun
- University of Kansas Medical Center, Department of Pathology and Laboratory Medicine, Kansas City, KS 66160, USA
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32
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He S, Yang S, Deng G, Liu M, Zhu H, Zhang W, Yan S, Quan L, Bai J, Xu N. Aurora kinase A induces miR-17-92 cluster through regulation of E2F1 transcription factor. Cell Mol Life Sci 2010; 67:2069-76. [PMID: 20300951 PMCID: PMC11115945 DOI: 10.1007/s00018-010-0340-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2009] [Revised: 01/07/2010] [Accepted: 02/11/2010] [Indexed: 01/07/2023]
Abstract
Aurora kinase A (AURKA) is an essential mitotic serine/threonine kinase and its abnormal expression is observed in many malignancies, yet the exact role for AURKA in tumorigenesis still remains elusive. Here, through a transcription factor array, we show that the transcription activity of E2F1 was increased by AURKA overexpression. Meanwhile, the E2F1 protein level was found to be upregulated and a correlation between AURKA and E2F1 expression was observed in cancer specimens. Further analysis revealed that AURKA increased E2F1 protein stability by inhibiting proteasome-dependent degradation of this protein. Additionally, a microRNA cluster, miR-17-92, was found to be upregulated upon AURKA overexpression, and this stimulation was largely repressed by E2F1 knockdown. Chromatin immunoprecipitation further demonstrated that AURKA enhanced E2F1 occupancy to the promoter of the miR-17-92 cluster. These data reveal a novel link between AURKA and microRNAs via the regulation of E2F1, providing new clues for understanding the role of AURKA in tumorigenesis.
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Affiliation(s)
- Shun He
- Laboratory of Cell and Molecular Biology and State Key Laboratory of Molecular Oncology, Cancer Institute and Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 17 Panjiayuan Nanli, Chaoyang District, PO Box 2258, Beijing, 100021 People’s Republic of China
| | - Shangbin Yang
- Laboratory of Cell and Molecular Biology and State Key Laboratory of Molecular Oncology, Cancer Institute and Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 17 Panjiayuan Nanli, Chaoyang District, PO Box 2258, Beijing, 100021 People’s Republic of China
| | - Guohua Deng
- Department of Pathology, Cancer Institute and Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100021 China
| | - Mei Liu
- Laboratory of Cell and Molecular Biology and State Key Laboratory of Molecular Oncology, Cancer Institute and Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 17 Panjiayuan Nanli, Chaoyang District, PO Box 2258, Beijing, 100021 People’s Republic of China
| | - Hongxia Zhu
- Laboratory of Cell and Molecular Biology and State Key Laboratory of Molecular Oncology, Cancer Institute and Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 17 Panjiayuan Nanli, Chaoyang District, PO Box 2258, Beijing, 100021 People’s Republic of China
| | - Wei Zhang
- Laboratory of Cell and Molecular Biology and State Key Laboratory of Molecular Oncology, Cancer Institute and Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 17 Panjiayuan Nanli, Chaoyang District, PO Box 2258, Beijing, 100021 People’s Republic of China
| | - Shuang Yan
- Laboratory of Cell and Molecular Biology and State Key Laboratory of Molecular Oncology, Cancer Institute and Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 17 Panjiayuan Nanli, Chaoyang District, PO Box 2258, Beijing, 100021 People’s Republic of China
| | - Lanping Quan
- Laboratory of Cell and Molecular Biology and State Key Laboratory of Molecular Oncology, Cancer Institute and Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 17 Panjiayuan Nanli, Chaoyang District, PO Box 2258, Beijing, 100021 People’s Republic of China
| | - Jinfeng Bai
- Laboratory of Cell and Molecular Biology and State Key Laboratory of Molecular Oncology, Cancer Institute and Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 17 Panjiayuan Nanli, Chaoyang District, PO Box 2258, Beijing, 100021 People’s Republic of China
| | - Ningzhi Xu
- Laboratory of Cell and Molecular Biology and State Key Laboratory of Molecular Oncology, Cancer Institute and Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, 17 Panjiayuan Nanli, Chaoyang District, PO Box 2258, Beijing, 100021 People’s Republic of China
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Wirt SE, Sage J. p107 in the public eye: an Rb understudy and more. Cell Div 2010; 5:9. [PMID: 20359370 PMCID: PMC2861648 DOI: 10.1186/1747-1028-5-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2010] [Accepted: 04/02/2010] [Indexed: 11/25/2022] Open
Abstract
p107 and its related family members Rb and p130 are critical regulators of cellular proliferation and tumorigenesis. Due to the extent of functional overlap within the Rb family, it has been difficult to assess which functions are exclusive to individual members and which are shared. Like its family members, p107 can bind a variety of cellular proteins to affect the expression of many target genes during cell cycle progression. Unlike Rb and p130, p107 is most highly expressed during the G1 to S phase transition of the cell cycle in actively dividing cells and accumulating evidence suggests a role for p107 during DNA replication. The specific roles for p107 during differentiation and development are less clear, although emerging studies suggest that it can cooperate with other Rb family members to control differentiation in multiple cell lineages. As a tumor suppressor, p107 is not as potent as Rb, yet studies in knockout mice have revealed some tumor suppressor functions in mice, depending on the context. In this review, we identify the unique and overlapping functions of p107 during the cell cycle, differentiation, and tumorigenesis.
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Affiliation(s)
- Stacey E Wirt
- Departments of Pediatrics and Genetics, Stanford Medical School, Stanford, CA 94305, USA.
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34
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Swiss VA, Casaccia P. Cell-context specific role of the E2F/Rb pathway in development and disease. Glia 2010; 58:377-90. [PMID: 19795505 DOI: 10.1002/glia.20933] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Development of the central nervous system (CNS) requires the generation of neuronal and glial cell subtypes in appropriate numbers, and this demands the careful coordination of cell-cycle exit, survival, and differentiation. The E2F/Rb pathway is critical for cell-cycle regulation and also modulates survival and differentiation of distinct cell types in the developing and adult CNS. In this review, we first present the specific temporal patterns of expression of the E2F and Rb family members during CNS development and then discuss the genetic ablation of single or multiple members of these two families. Overall, the available data suggest a time-dependent and cell-context specific role of E2F and Rb family members in the developing and adult CNS.
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Affiliation(s)
- Victoria A Swiss
- Department of Neuroscience and Genetics and Genomics, Mount Sinai School of Medicine, New York, New York 10029, USA
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35
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Abstract
We have established a novel production process which allows up to fourfold higher production of a model secreted protein, the human secreted alkaline phosphatase (SEAP), in Chinese hamster ovary (CHO) cells. A cytostatic production phase is established in which cell proliferation is inhibited or completely abolished. Such a cytostatic production phase is established by overexpression of the tumor suppressor genes p21, p27, or p53175P (a p53 mutant showing specific loss of apoptotic function) under transcriptional control of a tetracycline-repressible promoter (P(hCMV*-1)). In order to minimize complications due to possible clonal variation of selected, stable cell lines, our investigations are based on transiently transfected subpopulations, that have become a useful tool in industrial R&D. These subpopulations have been selected by flow cytometry for the expression of genes encoded on a dicistronic expression vector. These vectors contain a dicistronic expression unit consisting of the genes encoding the green fluorescent protein (GFP) or SEAP, followed by one of the cytostatic genes p21, p27 or p53175P encoded by the second cistron. p21, p27 as well as p53175P block the cell cycle of CHO cells in the G1-phase for a prolonged period. However, these G1-arrested cells remain viable and proliferation proficient upon repression of expression of the cytostatic gene. All three of the cytostatic genes studied provided similar regulation of proliferation, and also similar enhancements in SEAP production, suggesting that higher productivity may be a general and intrinsic feature of G1-phase arrested CHO cells. Overall productivity is most likely enhanced because growth-arrested cells do not need to devote cellular resources to biomass production.
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Affiliation(s)
- M Fussenegger
- Institute of Biotechnology, Swiss Federal Institute of Technology, ETH Zurich, CH-8093 Zurich, Switzerland
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36
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Nguyen CL, Münger K. Direct association of the HPV16 E7 oncoprotein with cyclin A/CDK2 and cyclin E/CDK2 complexes. Virology 2008; 380:21-5. [PMID: 18718623 DOI: 10.1016/j.virol.2008.07.017] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2008] [Revised: 04/30/2008] [Accepted: 07/21/2008] [Indexed: 12/17/2022]
Abstract
The human papillomavirus (HPV) E7 oncoprotein has been shown to associate with cyclin/CDK2 complexes. Here we present evidence that HPV E7 proteins can associate with cyclin A/CDK2 and cyclin E/CDK2 complexes in cells that lack retinoblastoma tumor suppressor family members through sequences outside of the core retinoblastoma tumor suppressor binding site. Moreover, we show that HPV16 E7 can directly associate with cyclin A/CDK2 and cyclin E/CDK2 complexes. These results suggest that cyclin/CDK2 complexes may be components of HPV E7-associated cellular complexes that do not contain retinoblastoma tumor suppressor family members.
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Affiliation(s)
- Christine L Nguyen
- Infectious Diseases Division, Channing Laboratories 861, Brigham and Women's Hospital, 181 Longwood Avenue, Boston, MA 02115, USA
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37
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Khan AM, Singer A. Biomarkers in cervical precancer management: the new frontiers. Future Oncol 2008; 4:515-24. [DOI: 10.2217/14796694.4.4.515] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The major cause of cervical cancer and its pre-invasive lesions is persistent infections with oncogenic human papillomavirus (HPV). Viral replication and integration in the cervix depends on the ordered expression of viral gene products, which can lead to overexpression of multiple molecular proteins or biomarkers. These novel biomarkers allow the monitoring of essential molecular events in histological or cytological specimens and are likely to improve the detection of lesions that have a high risk of progression in both primary screening and triage settings. This review focuses on these molecular markers and their role in the diagnosis and management of cervical dysplasia and cancer.
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Affiliation(s)
- Ashfaq M Khan
- Whittington Hospital NHS, Women’s Health, London N19 5NF, UK and, Institute of Child Health, University College London, London, UK
| | - Albert Singer
- Whittington Hospital NHS, Gynaecological Research, Women’s Health, London N19 5NF, UK
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38
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Yee JC, de Leon Gatti M, Philp RJ, Yap M, Hu WS. Genomic and proteomic exploration of CHO and hybridoma cells under sodium butyrate treatment. Biotechnol Bioeng 2008; 99:1186-204. [DOI: 10.1002/bit.21665] [Citation(s) in RCA: 100] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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39
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Yeh N, Miller JP, Gaur T, Capellini TD, Nikolich-Zugich J, de la Hoz C, Selleri L, Bromage TG, van Wijnen AJ, Stein GS, Lian JB, Vidal A, Koff A. Cooperation between p27 and p107 during endochondral ossification suggests a genetic pathway controlled by p27 and p130. Mol Cell Biol 2007; 27:5161-71. [PMID: 17502351 PMCID: PMC1951950 DOI: 10.1128/mcb.02431-06] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2006] [Revised: 02/21/2007] [Accepted: 05/02/2007] [Indexed: 02/05/2023] Open
Abstract
Pocket proteins and cyclin-dependent kinase (CDK) inhibitors negatively regulate cell proliferation and can promote differentiation. However, which members of these gene families, which cell type they interact in, and what they do to promote differentiation in that cell type during mouse development are largely unknown. To identify the cell types in which p107 and p27 interact, we generated compound mutant mice. These mice were null for p107 and had a deletion in p27 that prevented its binding to cyclin-CDK complexes. Although a fraction of these animals survived into adulthood and looked similar to single p27 mutant mice, a larger number of animals died at birth or within a few weeks thereafter. These animals displayed defects in chondrocyte maturation and endochondral bone formation. Proliferation of chondrocytes was increased, and ectopic ossification was observed. Uncommitted mouse embryo fibroblasts could be induced into the chondrocytic lineage ex vivo, but these cells failed to mature normally. These results demonstrate that p27 carries out overlapping functions with p107 in controlling cell cycle exit during chondrocyte maturation. The phenotypic similarities between p107(-/-) p27(D51/D51) and p107(-/-) p130(-/-) mice and the cells derived from them suggest that p27 and p130 act in an analogous pathway during chondrocyte maturation.
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Affiliation(s)
- Nancy Yeh
- Sloan-Kettering Institute, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA
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40
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Wang B, Omar A, Angelovska T, Drobic V, Rattan SG, Jones SC, Dixon IMC. Regulation of collagen synthesis by inhibitory Smad7 in cardiac myofibroblasts. Am J Physiol Heart Circ Physiol 2007; 293:H1282-90. [PMID: 17513491 DOI: 10.1152/ajpheart.00910.2006] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Transforming growth factor-beta(1) (TGF-beta(1)) signal and downstream Smads play an important role in tissue fibrosis and matrix remodeling in various etiologies of heart failure. Inhibitory Smad7 (I-Smad7) is an inducible regulatory Smad protein that antagonizes TGF-beta(1) signal mediated via direct abrogation of R-Smad phosphorylation. The effect of ectopic I-Smad7 on net collagen production was investigated using hydroxyproline assay. Adenovirus-mediated I-Smad7 gene (at 100 multiplicity of infection) transfer was associated with significant decrease of collagen synthesis in the presence and absence of TGF-beta(1) in primary rat cardiac myofibroblasts. In I-Smad7-infected cells, we also observed the ablation of TGF-beta(1)-induced R-Smad2 phosphorylation vs. LacZ controls. Overdriven I-Smad7 was associated with significantly increased expression of immunoreactive 65-kDa matrix metalloproteinase-2 (MMP-2) protein in culture medium of myofibroblast compared with LacZ-infected cells. Expression of the 72-kDa MMP-2 variant, e.g., the inactive form, was not altered by exogenous I-Smad7 transfection/overexpression. Furthermore, I-Smad7 overexpression was associated with a significant increase and decrease in expression of p27 and phospho-Rb protein, respectively, as well as reduced [(3)H]thymidine incorporation vs. Ad-LacZ-infected controls. We suggest that negative modulation of R-Smad phosphorylation by ectopic I-Smad7 may contribute to the downregulation of collagen in cardiac myofibroblasts and may suppress the proliferation of these cells. Thus treatments targeting the collagen deposition by overexpression of I-Smad7 may provide a new therapeutic strategy for cardiac fibrosis.
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Affiliation(s)
- Baiqiu Wang
- Institute of Cardiovascular Science, St. Boniface General Hospital Research Centre and Department of Physiology, University of Manitoba, Winnipeg, Canada
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41
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Wenzel PL, Wu L, de Bruin A, Chong JL, Chen WY, Dureska G, Sites E, Pan T, Sharma A, Huang K, Ridgway R, Mosaliganti K, Sharp R, Machiraju R, Saltz J, Yamamoto H, Cross JC, Robinson ML, Leone G. Rb is critical in a mammalian tissue stem cell population. Genes Dev 2007; 21:85-97. [PMID: 17210791 PMCID: PMC1759903 DOI: 10.1101/gad.1485307] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The inactivation of the retinoblastoma (Rb) tumor suppressor gene in mice results in ectopic proliferation, apoptosis, and impaired differentiation in extraembryonic, neural, and erythroid lineages, culminating in fetal death by embryonic day 15.5 (E15.5). Here we show that the specific loss of Rb in trophoblast stem (TS) cells, but not in trophoblast derivatives, leads to an overexpansion of trophoblasts, a disruption of placental architecture, and fetal death by E15.5. Despite profound placental abnormalities, fetal tissues appeared remarkably normal, suggesting that the full manifestation of fetal phenotypes requires the loss of Rb in both extraembryonic and fetal tissues. Loss of Rb resulted in an increase of E2f3 expression, and the combined ablation of Rb and E2f3 significantly suppressed Rb mutant phenotypes. This rescue appears to be cell autonomous since the inactivation of Rb and E2f3 in TS cells restored placental development and extended the life of embryos to E17.5. Taken together, these results demonstrate that loss of Rb in TS cells is the defining event causing lethality of Rb(-/-) embryos and reveal the convergence of extraembryonic and fetal functions of Rb in neural and erythroid development. We conclude that the Rb pathway plays a critical role in the maintenance of a mammalian stem cell population.
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Affiliation(s)
- Pamela L. Wenzel
- Human Cancer Genetics Program, Department of Molecular Virology, Immunology and Medical Genetics, College of Medicine, The Ohio State University, Columbus, Ohio 43210, USA
- Department of Molecular Genetics, College of Biological Sciences, The Ohio State University, Columbus, Ohio 43210, USA
- Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, USA
| | - Lizhao Wu
- Human Cancer Genetics Program, Department of Molecular Virology, Immunology and Medical Genetics, College of Medicine, The Ohio State University, Columbus, Ohio 43210, USA
- Department of Molecular Genetics, College of Biological Sciences, The Ohio State University, Columbus, Ohio 43210, USA
- Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, USA
| | - Alain de Bruin
- Human Cancer Genetics Program, Department of Molecular Virology, Immunology and Medical Genetics, College of Medicine, The Ohio State University, Columbus, Ohio 43210, USA
- Department of Molecular Genetics, College of Biological Sciences, The Ohio State University, Columbus, Ohio 43210, USA
- Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, USA
| | - Jean-Leon Chong
- Human Cancer Genetics Program, Department of Molecular Virology, Immunology and Medical Genetics, College of Medicine, The Ohio State University, Columbus, Ohio 43210, USA
- Department of Molecular Genetics, College of Biological Sciences, The Ohio State University, Columbus, Ohio 43210, USA
- Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, USA
| | - Wen-Yi Chen
- Human Cancer Genetics Program, Department of Molecular Virology, Immunology and Medical Genetics, College of Medicine, The Ohio State University, Columbus, Ohio 43210, USA
- Department of Molecular Genetics, College of Biological Sciences, The Ohio State University, Columbus, Ohio 43210, USA
- Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, USA
| | - Geoffrey Dureska
- Human Cancer Genetics Program, Department of Molecular Virology, Immunology and Medical Genetics, College of Medicine, The Ohio State University, Columbus, Ohio 43210, USA
- Department of Molecular Genetics, College of Biological Sciences, The Ohio State University, Columbus, Ohio 43210, USA
- Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, USA
| | - Emily Sites
- Human Cancer Genetics Program, Department of Molecular Virology, Immunology and Medical Genetics, College of Medicine, The Ohio State University, Columbus, Ohio 43210, USA
- Department of Molecular Genetics, College of Biological Sciences, The Ohio State University, Columbus, Ohio 43210, USA
- Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, USA
| | - Tony Pan
- Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, USA
- Biomedical Informatics, Department of Pathology, College of Medicine, The Ohio State University, Columbus, Ohio 43210, USA
| | - Ashish Sharma
- Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, USA
- Biomedical Informatics, Department of Pathology, College of Medicine, The Ohio State University, Columbus, Ohio 43210, USA
| | - Kun Huang
- Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, USA
- Biomedical Informatics, Department of Pathology, College of Medicine, The Ohio State University, Columbus, Ohio 43210, USA
| | - Randall Ridgway
- Department of Computer Science and Engineering, The Ohio State University, Columbus, Ohio 43210, USA
| | - Kishore Mosaliganti
- Department of Computer Science and Engineering, The Ohio State University, Columbus, Ohio 43210, USA
| | - Richard Sharp
- Department of Computer Science and Engineering, The Ohio State University, Columbus, Ohio 43210, USA
| | - Raghu Machiraju
- Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, USA
- Biomedical Informatics, Department of Pathology, College of Medicine, The Ohio State University, Columbus, Ohio 43210, USA
- Department of Computer Science and Engineering, The Ohio State University, Columbus, Ohio 43210, USA
| | - Joel Saltz
- Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, USA
- Biomedical Informatics, Department of Pathology, College of Medicine, The Ohio State University, Columbus, Ohio 43210, USA
| | - Hideyuki Yamamoto
- Department of Biochemistry and Molecular Biology, University of Calgary Faculty of Medicine, Calgary, Alberta T2N 4N1, Canada
| | - James C. Cross
- Department of Biochemistry and Molecular Biology, University of Calgary Faculty of Medicine, Calgary, Alberta T2N 4N1, Canada
| | - Michael L. Robinson
- Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, USA
- Division of Molecular and Human Genetics, Children’s Research Institute, Columbus, Ohio 43205, USA
- Department of Pediatrics, The Ohio State University, Columbus, Ohio 43210, USA
- E-MAIL ; FAX (513) 529-6900
| | - Gustavo Leone
- Human Cancer Genetics Program, Department of Molecular Virology, Immunology and Medical Genetics, College of Medicine, The Ohio State University, Columbus, Ohio 43210, USA
- Department of Molecular Genetics, College of Biological Sciences, The Ohio State University, Columbus, Ohio 43210, USA
- Comprehensive Cancer Center, The Ohio State University, Columbus, Ohio 43210, USA
- Corresponding authors.E-MAIL ; FAX (614) 292-3312
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42
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van Drogen F, Sangfelt O, Malyukova A, Matskova L, Yeh E, Means AR, Reed SI. Ubiquitylation of cyclin E requires the sequential function of SCF complexes containing distinct hCdc4 isoforms. Mol Cell 2006; 23:37-48. [PMID: 16818231 DOI: 10.1016/j.molcel.2006.05.020] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2005] [Revised: 03/22/2006] [Accepted: 05/10/2006] [Indexed: 02/02/2023]
Abstract
Cyclin E, an activator of cyclin-dependent kinase 2 (Cdk2), is targeted for proteasomal degradation by phosphorylation-dependent multiubiquitylation via the ubiquitin ligase SCF(hCdc4). SCF ubiquitin ligases are composed of a core of conserved subunits and one variable subunit (an F box protein) involved in substrate recognition. We show here that multiubiquitylation of cyclin E requires the sequential function of two distinct splice variant isoforms of the F box protein hCdc4 known as alpha and gamma. SCF(hCdc4alpha) binds a complex containing cyclin E, Cdk2, and the prolyl cis/trans isomerase Pin1 and promotes the activity of Pin1 without directly ubiquitylating cyclin E. However, due to the action of this SCF(hCdc4alpha)-Pin1 complex, cyclin E becomes an efficient ubiquitylation substrate of SCF(hCdc4gamma). Furthermore, in the context of Cdc4alpha and cyclin E, mutational data suggest that Pin1 isomerizes a noncanonical proline-proline bond, with the possibility that Cdc4alpha may serve as a cofactor for altering the specificity of Pin1.
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Affiliation(s)
- Frank van Drogen
- Department of Molecular Biology, The Scripps Research Institute, La Jolla, California 92037, USA
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43
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Spruck C, Sun D, Fiegl H, Marth C, Mueller-Holzner E, Goebel G, Widschwendter M, Reed SI. Detection of Low Molecular Weight Derivatives of Cyclin E1 Is a Function of Cyclin E1 Protein Levels in Breast Cancer. Cancer Res 2006; 66:7355-60. [PMID: 16849587 DOI: 10.1158/0008-5472.can-05-3240] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cyclin E1 regulates the initiation of the S phase program in the mammalian cell division cycle. In normal cells, cyclin E1 protein expression is tightly controlled through a combination of transcriptional and proteolytic regulatory processes. However, in many types of human tumor, cyclin E1 expression is frequently dysregulated, including overexpression, nonperiodic expression relative to cell division, and generation of low molecular weight (LMW) derivatives. LMW derivatives of cyclin E1 have been proposed to be generated by the in vivo proteolytic cleavage of the full-length cyclin E1 protein by a yet to be identified tumor-specific protease. Recently, it was suggested that overexpression of full-length or LMW derivatives of cyclin E1 are independent variables associated with poor outcome in patients with breast cancer. However, we have extensively analyzed cyclin E1 protein expression in primary breast tumors and breast tumor-derived cell lines and found that the ability to detect LMW derivatives of cyclin E1 correlates only with the level of cyclin E1 protein. When cyclin E1 levels on Western blots are normalized, LMW derivatives of cyclin E1 were observed at roughly equal levels in all primary breast tumors, breast tumor-derived cell lines, immortalized nontransformed human mammary epithelial cells, and normal breast tissue. Therefore, the detection of LMW derivatives of cyclin E1 is likely a function of cyclin E1 protein levels, and the activity of the proteolytic machinery responsible for their generation is not a tumor-specific property.
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Affiliation(s)
- Charles Spruck
- Department of Molecular Biology, The Scripps Research Institute, La Jolla, California 92037, USA
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44
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Abstract
The F-box-containing protein Skp2 plays a critical role in coordinating the G1/S transition and progression through the S phase of the mammalian cell cycle. Skp2 is overexpressed in a broad spectrum of human cancers and the expression level correlates with tumor malignancy. However, the Skp2 gene is neither amplified nor rearranged in most human cancers and the underlying mechanism of Skp2 overexpression remains poorly understood. We show here that the Skp2 gene contains a functional E2F response element (hSRE2). Ectopic expression of E2F1 induces expression of the endogenous Skp2 gene in human fibroblast cells, whereas antisense-mediated knockdown of E2F1 in human tumor cell lines reduces expression of endogenous Skp2 gene. The hSRE2 element not only participates in activation of Skp2 promoter function during normal cell cycle progression into S phase, it is also required for the high-level Skp2 gene expression in many human tumor cell lines. These results reveal Skp2 as a novel target for E2F regulation that is disrupted in several human tumor cell lines.
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Affiliation(s)
| | - C Wang
- Correspondence: Associate Professor C Wang, Center for Molecular Biology of Oral Diseases, University of Illinois at Chicago, 801 South Paulina Street, Room 530E, m/c 860, Chicago, IL 60612, USA. E-mail:
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45
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Cheng KY, Noble MEM, Skamnaki V, Brown NR, Lowe ED, Kontogiannis L, Shen K, Cole PA, Siligardi G, Johnson LN. The role of the phospho-CDK2/cyclin A recruitment site in substrate recognition. J Biol Chem 2006; 281:23167-79. [PMID: 16707497 DOI: 10.1074/jbc.m600480200] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Phospho-CDK2/cyclin A, a kinase that is active in cell cycle S phase, contains an RXL substrate recognition site that is over 40 A from the catalytic site. The role of this recruitment site, which enhances substrate affinity and catalytic efficiency, has been investigated using peptides derived from the natural substrates, namely CDC6 and p107, and a bispeptide inhibitor in which the gamma-phosphate of ATP is covalently attached by a linker to the CDC6 substrate peptide. X-ray studies with a 30-residue CDC6 peptide in complex with pCDK2/cyclin A showed binding of a dodecamer peptide at the recruitment site and a heptapeptide at the catalytic site, but no density for the linking 11 residues. Kinetic studies established that the CDC6 peptide had an 18-fold lower Km compared with heptapeptide substrate and that this effect required the recruitment peptide to be covalently linked to the substrate peptide. X-ray studies with the CDC6 bispeptide showed binding of the dodecamer at the recruitment site and the modified ATP in two alternative conformations at the catalytic site. The CDC6 bispeptide was a potent inhibitor competitive with both ATP and peptide substrate of pCDK2/cyclin A activity against a heptapeptide substrate (Ki = 0.83 nm) but less effective against RXL-containing substrates. We discuss how localization at the recruitment site (KD 0.4 microm) leads to increased catalytic efficiency and the design of a potent inhibitor. The notion of a flexible linker between the sites, which must have more than a minimal number of residues, provides an explanation for recognition and discrimination against different substrates.
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Affiliation(s)
- Kin-Yip Cheng
- Laboratory of Molecular Biophysics, Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom
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46
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Abstract
In yeast, a single cyclin-dependent kinase (Cdk) is able to regulate diverse cell cycle transitions (S and M phases) by associating with multiple stage-specific cyclins. The evolution of multicellular organisms brought additional layers of cell cycle regulation in the form of numerous Cdks, cyclins and Cdk inhibitors to reflect the higher levels of organismal complexity. Our current knowledge about the mammalian cell cycle emerged from early experiments using human and rodent cell lines, from which we built the current textbook model of cell cycle regulation. In this model, the functions of different cyclin/Cdk complexes were thought to be specific for each cell cycle phase. In the last decade, studies using genetically engineered mice in which cell cycle regulators were targeted revealed many surprises. We discovered the in vivo functions of cell cycle proteins within the context of a living animal and whether they are essential for animal development. In this review, we discuss first the textbook model of cell cycle regulation, followed by a global overview of data obtained from different mouse models. We describe the similarities and differences between the phenotypes of different mouse models including embryonic lethality, sterility, hematopoietic, pancreatic, and placental defects. We also describe the role of key cell cycle regulators in the development of tumors in mice, and the implications of these data for human cancer. Furthermore, animal models in which two or more genes are ablated revealed which cell cycle regulators interact genetically and functionally complement each other. We discuss for example the interaction of cyclin D1 and p27 and the compensation of Cdk2 by Cdc2. We also focus on new functions discovered for certain cell cycle regulators such as the regulation of S phase by Cdc2 and the role of p27 in regulating cell migration. Finally, we conclude the chapter by discussing the limitations of animal models and to what extent can the recent findings be reconciled with the past work to come up with a new model for cell cycle regulation with high levels of redundancy among the molecular players.
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Affiliation(s)
- Eiman Aleem
- National Cancer Institute, Mouse Cancer Genetics Program, NCI-Frederick, MD 21702-1201, USA
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47
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Philimonenko AA, Hodný Z, Jackson DA, Hozák P. The microarchitecture of DNA replication domains. Histochem Cell Biol 2005; 125:103-17. [PMID: 16247614 DOI: 10.1007/s00418-005-0090-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/20/2005] [Indexed: 02/07/2023]
Abstract
Most DNA synthesis in HeLa cell nucleus is concentrated in discrete foci. These synthetic sites can be identified by electron microscopy after allowing permeabilized cells to elongate nascent DNA in the presence of biotin-dUTP. Biotin incorporated into nascent DNA can be then immunolabeled with gold particles. Two types of DNA synthetic sites/replication factories can be distinguished at ultrastructural level: (1) electron-dense structures--replication bodies (RB), and (2) focal replication sites with no distinct underlying structure--replication foci (RF). The protein composition of these synthetic sites was studied using double immunogold labeling. We have found that both structures contain (a) proteins involved in DNA replication (DNA polymerase alpha, PCNA), (b) regulators of the cell cycle (cyclin A, cdk2), and (c) RNA processing components like Sm and SS-B/La auto antigens, p80-coilin, hnRNPs A1 and C1/C2. However, at least four regulatory and structural proteins (Cdk1, cyclin B1, PML and lamin B1) differ in their presence in RB and RF. Moreover, in contrast to RF, RB have structural organization. For example, while DNA polymerase alpha, PCNA and hnRNP A1 were diffusely spread throughout RB, hnRNP C1/C2 was found only at the very outside. Surprisingly, RB contained only small amounts of DNA. In conclusion, synthetic sites of both types contain similar but not the same sets of proteins. RB, however, have more developed microarchitecture, apparently with specific functional zones. This data suggest possible differences in genome regions replicated by these two types of replication factories.
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Affiliation(s)
- Anatoly A Philimonenko
- Institute of Experimental Medicine, Academy of Sciences of the Czech Republic, Vídenská 1083, 142 20, Prague 4-Krc, Czech Republic
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48
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Abstract
Dyer and colleagues examine the most promising preclinical models that recapitulate the molecular, genetic, and cellular features of retinoblastoma.
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Affiliation(s)
- Michael A Dyer
- Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, Tennessee, United States of America.
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49
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Qiao X, Bhuiya TA, Spitzer M. Differentiating high-grade cervical intraepithelial lesion from atrophy in postmenopausal women using Ki-67, cyclin E, and p16 immunohistochemical analysis. J Low Genit Tract Dis 2005; 9:100-7. [PMID: 15870531 DOI: 10.1097/00128360-200504000-00006] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
OBJECTIVE In postmenopausal women, differentiating high-grade cervical intraepithelial neoplasia (CIN 2,3) from atrophic uterine cervical squamous epithelium histologically may pose a diagnostic challenge. Recent studies have indicated the value of using a combination of Ki-67, cyclin E, and p16 immunohistochemical analysis in recognizing CIN 2,3. In this study, we compared the staining features of Ki-67, cyclin E, and p16 in cervix specimens from postmenopausal women to distinguish CIN 2,3 from atrophy. METHODS Twenty-six formalin-fixed paraffin-embedded archival cervical specimens (4 biopsy, 8 laser cone, and 14 total hysterectomy samples) were selected from 25 women 50 to 80 years of age (mean = 64 years). Cases included CIN 2,3 (n = 10), atrophy (n = 9), and coexistent CIN 2,3 and atrophy (n = 6). Slides were stained with monoclonal antibodies to Ki-67, cyclin E, and p16 using the avidin-biotin-peroxidase method. Strength of staining was graded as 1+ to 3+. Pattern of staining was described as diffuse, patchy, or scattered. Ki-67 staining restricted to the basal/parabasal zone was scored as negative. RESULTS All CIN 2,3 cases demonstrated variable positivity for Ki-67, cyclin E, and p16. Most CIN 2,3 cases showed strong p16 (81.3%) and Ki-67 (75.0%) reactivity, while only 31.3% of them showed strong cyclin E activity. Some CIN 2,3 cases demonstrated strong p16 but weak Ki-61 and cyclin E reactivity. All atrophic epithelia were negative for p16, cyclin E, and Ki-67. In coexistent CIN 2,3 and atrophy cases, the three-antibody panel clearly demarcated the transition from benign to neoplastic epithelia. CONCLUSION P16 is the most valuable marker followed by Ki-67 for differentiating CIN 2,3. While cyclin E appears to add limited value on these two markers. Therefore, although the three-antibody immunohistochemical panel (p16, Ki-67, and cyclin E) can be a valuable adjunct to routine hematoxylin-eosin staining, it is also possible to use the two-antibody panel (p16 and Ki-67) to effectively distinguish CIN 2,3 from atrophy in postmenopausal women.
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Affiliation(s)
- Xiaoying Qiao
- Department of Pathology, Long Island Jewish Medical Center, New Hyde Park, New York, USA.
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50
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Zong H, Li Z, Liu L, Hong Y, Yun X, Jiang J, Chi Y, Wang H, Shen X, Hu Y, Niu Z, Gu J. Cyclin-dependent kinase 11p58interacts with HBO1 and enhances its histone acetyltransferase activity. FEBS Lett 2005; 579:3579-88. [PMID: 15963510 DOI: 10.1016/j.febslet.2005.05.039] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2005] [Revised: 05/15/2005] [Accepted: 05/18/2005] [Indexed: 11/30/2022]
Abstract
CDK11(p58), a 58kDa protein of the PITSLRE kinase family, plays an important role in cell cycle progression, and is closely related to cell apoptosis. To gain further insight into the function of CDK11(p58), we screened a human fetal liver cDNA library for its interacting proteins using the yeast two-hybrid system. Here we report that histone acetyltransferase (HAT) HBO1, a MYST family protein, interacts with CDK11(p58) in vitro and in vivo. CDK11(p58) and HBO1 colocalize in the cell nucleus. Recombinant CDK11(p58) enhances the HAT activity of HBO1 significantly in vitro. Meanwhile, overexpression of CDK11(p58) in mammalian cells leads to the enhanced HAT activity of HBO1 towards free histones. Thus, we conclude that CDK11(p58) is a new interacting protein and a novel regulator of HBO1. Both of the proteins may be involved in the regulation of eukaryotic transcription.
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Affiliation(s)
- Hongliang Zong
- State Key Laboratory of Genetic Engineering & Gene Research Center, Shanghai Medical College of Fudan University, P.O. Box 103, No. 138 Yi Xue Yuan Road, 200032 Shanghai, People's Republic of China
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